Heat-sensitive recording materials and phenol compounds

ABSTRACT

Heat-sensitive recording materials contain an electron-donating chromogenic compound and an electron-attracting compound. The recording materials also contain at least one compound represented by the following formula: ##STR1## wherein R 1  and R 3  mean a hydrogen atom or an alkyl, aralkyl or aryl group, R 2  and R 4  denote an alkyl, alkenyl, aralkyl or aryl group, X 1 , X 2 , Y 1  and Y 2  stand for an oxygen or a sulfur atom, and --Z 1  -- and --Z 2  -- are a specific aromatic group. Also provided are phenol compounds represented by the following formula: ##STR2## wherein R 1 , R 2 , X 1  and Y 1  have the same meanings as defined above; R 5  and R 6  are a hydrogen or halogen atom or an alkyl, alkoxy, aralkyl, aryl or hydroxyl group; p and q stand for an integer of 1-4; R 5  and R 6  may be either the same or different when p and q represent an integer of 2 or greater; and --Z 3  -- means a specific divalent group.

BACKGROUND OF THE INVENTION

1. Field of the Invention

This invention relates to heat-sensitive recording materials, and especially to heat-sensitive recording materials capable of producing color images with improved storage stability. This invention is also concerned with novel phenol compounds, and in particular with novel phenol compounds useful as color-developing agents or additives for recording materials (for example, heat-sensitive recording materials) or as monomers or additives for high molecular materials.

Heat-sensitive recording materials making use of the color-producing reaction between an electron-donating chromogenic compound and an electron-attracting compound (color-developing agent) have been well known conventionally (for example, Japanese Patent Publication Nos. 4160/1968 and 14039/1970). These heat-sensitive recording materials are relatively inexpensive and, moreover, have the merit that recording equipment therefor are compact and maintenance-free. They have hence found utility in a wide variety of fields such as facsimiles, recorders and printers. PG,3

As electron-attracting compounds, phenol compounds are widely used. Among these, 2,2-bis(4'-hydroxyphenyl)propane (also called "bisphenol A") is extensively used for its availability at low cost. Bisphenol A is, however, accompanied by the drawback that heat-recording materials using bisphenol A as an electron-attracting compound cannot produce color images with good storage stability. In addition, heat-sensitive recording materials with bisphenol A as an electron-attracting compound also involve the drawback that their color-producing sensitivity is low. Heat-sensitive recording materials using, as an electron-attracting compound, a phenol compound other than bisphenol A have also been proposed, for example, 4-hydroxybenzoate esters (Japanese Patent Laid-Open No. 144193/1981 and Japanese Patent Publication No. 30640/1989), aralkyloxyphenols (Japanese Patent Publication No. 31678/1990 and Japanese Patent Laid-Open No. 225789/1985) and hydroxybenzophenones (Japanese Patent Laid-Open No. 193388/1982).

The use of 4-hydroxybenzoate esters, for example, benzyl 4-hydroxybenzoate as an electron-attracting compound, however, leads to the drawback that the density of a produced color image drops with time. It is also accompanied by the drawback that white crystals of benzyl 4-hydroxybenzoate are formed on the produced color image thereby to present a powdered appearance (the so-called "whitening phenomenon"). The use of aralkyloxyphenols, for example, 4-benzyloxyphenol as an electron-attracting compound also results in the drawback that the density of a produced color image drops as time goes on. When hydroxybenzophenones, for example, 4-hydroxybenzophenone is used as an electron-attracting compound, the resulting color image has poor storage stability (for example, hydrothermoresistance and waterproofness) so that they are not considered to have sufficient quality or properties for practical use.

On other hand, heat-sensitive recording materials containing--as a method for improving the color-producing sensitivity--a thermofusible compound (sensitizer) in addition to an electron-donating chromogenic compound and an electron-attracting compound are also widely used. Proposed as thermofusible compounds include terphenyls (Japanese Patent Publication No. 7958/1988), benzyl 4-benzyloxybenzoate (Japanese Patent Publication No. 30878/1988), naphthol derivatives (Japanese patent Publication No. 42590/1988), aminophenol derivatives (Japanese Patent Laid-Open No. 211494/1983), benzylbiphenyls (Japanese Patent Publication No. 11437/1990), diaryloxyalkane derivatives (Japanese Patent Laid-Open Nos. 56588/1985 and 16888/1986), oxalate ester derivatives (Japanese Patent Laid-Open No. 1583/1989), etc. However, it is the current situations that, although heat-sensitive recording materials containing one or more of these thermofusible compounds have been improved to some extent in color-producing sensitivity, they are accompanied by the problem of the extremely poor storage stability of produced color images, said storage stability being usually still inferior to that of color image produced without the addition of any thermofusible compound.

Accordingly, there is now a strong demand for the provision of heat-sensitive recording materials free of the drawbacks or problems described above, namely, for the provision of heat-sensitive recording materials capable of producing color images with excellent storage stability and, further, heat-sensitive recording materials having good color-producing sensitivity and capable of producing color images with excellent storage stability.

SUMMARY OF THE INVENTION

An object of this invention is, therefore, to provide a heat-sensitive recording material significantly improved in the storage stability of resulting color images. Another object of this invention is to provide a heat-sensitive recording material which is good in color-producing sensitivity and is excellent in the storage stability of resulting color images. A further object of this invention is to provide a novel phenol compound useful as a color-developing agent or an additive for heat-sensitive recording materials.

With a view toward meeting the demand described above, the present inventors have conducted extensive research on heat-sensitive recording materials and also on electron-attracting compounds and additives for heat-sensitive recording materials.

In one aspect of this invention, there is thus provided a heat-sensitive recording material containing an electron-donating chromogenic compound and an electron-attracting compound, comprising at least one of the compounds represented by the following formula (1) or (2): ##STR3## wherein R₁ and R₃ individually mean a hydrogen atom or an alkyl, aralkyl or aryl group, R₂ and R₄ individually denote an alkyl, alkenyl, aralkyl or aryl group, X₁, X₂, Y₁ and Y₂ stand for an oxygen or a sulfur atom, and --Z₁ -- and --Z₂ are a group represented by the following formula (i) or (ii): ##STR4## wherein R₅, R₆ and R₇ individually mean a hydrogen or halogen atom or an alkyl, alkoxy, aralkyl, aryl or hydroxyl group, p, q and r stand for an integer of 1-4, R₅, R₆ and R₇ may be either the same or different when p, q and r individually represent an integer of 2 or greater, the rings A and A' individually denote a benzene or naphthalene ring, the ring D represents a naphthalene ring, and --B-- represents a group containing at least one group selected from the class consisting of --R₈ CR₉ -- (in which R₈ and R₉ individually represent a hydrogen atom or an alkyl, trifluoromethyl or aryl group or are combined together to form a ring), --O--, --S--, a phenylene group, --CO--, a single bond, --C_(m) H_(2m) --, m being an integer of 2-10, --CR₁₀ ═CR₁₁ -- (in which R₁₀ and R₁₁ are individually a hydrogen atom or an alkyl or aryl group), --SO--, and --SO₂ --.

In another aspect of this invention, there is also provided a phenol compound represented by the following formula (3): ##STR5## wherein R₁ means a hydrogen atom or an alkyl, aralkyl or aryl group, R₂ denotes an alkyl, alkenyl, aralkyl or aryl group, R₅ and R₆ are a hydrogen or halogen atom or an alkyl, alkoxy, aralkyl, aryl or hydroxyl group, p and q stand for an integer of 1-4, R₅ and R₆ may be either the same or different when p and q individually represent an integer of 2 or greater, X₁ and Y₁ individually represent an oxygen or sulfur atom, and --Z₃ -- means a group containing at least one group selected from the class consisting of --R₈ CR₉ -- (in which R₈ and R₉ individually represent a hydrogen atom or an alkyl, trifluoromethyl or aryl group or are combined together to form a ring), --O--, --S--, a phenylene group, --CO--, --C_(m) H_(2m) --, m being an integer of 2-10, --CR₁₀ ═CR₁₁ -- (in which R₁₀ and R₁₁ are individually a hydrogen atom or an alkyl or aryl group), --SO-- and --SO₂ --.

The heat-sensitive recording material according to the present invention ca promptly produce a color at low temperatures so that it is suitable for use in high-speed recording. Moreover, the color image so produced has excellent storage stability (heat resistance, hydrothermoresistance, waterproofness and oil resistance).

DETAILED DESCRIPTION OF THE INVENTION AND PREFERRED EMBODIMENTS

Where the ring A and/or the ring A' in the group represented b the formula (i) in the compound according to the present invention, said compound being represented by the formula (1) or (2), is a benzene ring, the position of substitution by each phenolic hydroxyl group and/or carbamate group substituted on the benzene ring may be preferably the ortho-, meta- or para-position, more preferably the meta- or para-position, both relative to the --B-- group in the formula (i). Where the ring A and/or ring A' is a naphthalene ring, the position of substitution by each phenolic hydroxyl group and/or carbamate group substituted on the naphthalene ring may be preferably the 2-, 3-, 4-, 5-, 6-, 7- or 8-position when the --B-- group is substituted to the 1-position (α-position) of the naphthalene ring. When the --B-- group is substituted to the 2-position (β-position) of the naphthalene ring, on the other hand, the position of substitution by each phenolic hydroxyl group and/or carbamate group substituted on the naphthalene ring may be preferably the 1-, 3-, 4-, 5-, 6-, 7- or 8-position.

In the naphthalene ring in the group represented by the formula (ii), the positions of substitution by phenolic hydroxyl and/or carbamate groups may be on the same benzene ring or the different benzene rings in the naphthalene ring.

In the compound represented by the formula (1) or (2), R₁ and R₃ are a hydrogen atom or an alkyl, aralkyl or aryl group; preferably a hydrogen atom or a C₁₋₂₀ alkyl, C₅₋₁₄ cycloalkyl, C₇₋₂₀ aralkyl or substituted or unsubstituted phenyl group; more preferably a hydrogen atom or a C₁₋₄ alkyl, cyclopentyl, cyclohexyl, cycloheptyl, benzyl or phenyl group; still more preferably a hydrogen atom or a C₁₋₄ alkyl group; most preferably a hydrogen atom.

In the compound represented by the formula (1) or (2), R₂ and R₄ are an alkyl, alkenyl, aralkyl or aryl group; preferably a substituted or unsubstituted alkyl, substituted or unsubstituted cycloalkyl, substituted or unsubstituted alkenyl, substituted or unsubstituted cycloalkenyl, substituted or unsubstituted aralkyl, substituted or unsubstituted phenyl, substituted or unsubstituted naphthyl, or substituted or unsubstituted heteroaromatic group.

The alkyl and alkenyl groups represented by R₂ or R₄ may contain one or more substituents, for example, may be monosubstituted or multisubstituted by substituent(s) such as C₁₋₂₀ alkoxy, C₂₋₂₀ alkoxyalkyloxy, C₂₋₂₀ alkenyloxy, C₇₋₂₀ aralkyloxy, C₈₋₂₀ aralkyloxyalkoxy, C₆₋₂₀ aryloxy, C₇₋₂₀ aryloxyalkoxy and/or hetero-atom-containing cycloalkyl group(s) and/or halogen atom(s).

Further, the aryl groups contained in these substituents may be substituted further by one or more C₁₋₆ alkyl, C₁₋₆ alkoxy, C₇₋₁₀ aralkyl, C₇₋₁₀ aralkyloxy and/or hydroxyl groups and/or one or more halogen atoms.

The aryl group in the aralkyl or aryl group represented by R₂ or R₄ may contain one or more substituents, for example, one or more C₁₋₂₀ alkyl, C₂₋₂₀ alkenyl, C₇₋₁₆ aralkyl, C₆₋₁₆ aryl, C₁₋₂₀ alkoxy, C₂₋₂₀ alkoxyalkyl, C₂₋₂₀ alkoxyalkyloxy, C₂₋₂₀ alkenyloxy, C₃₋₂₀ alkenyloxyalkyl, C₃₋₂₀ alkenyloxyalkyloxy, C₇₋₂₀ aralkyloxy, C₈₋₂₀ aralkyloxyalkyl, C₈₋₂₀ aralkyloxyalkyloxy, C₆₋₂₀ aryloxy, C₇₋₂₀ aryloxyalkyl, C₇₋₂₀ aryloxyalkyloxy, C₂₋₂₀ alkylcarbonyl, C₃₋₂₀ alkenylcarbonyl, C₈₋₂₀ aralkylcarbonyl, C₇₋₂₀ arylcarbonyl, C₂₋₂₀ alkoxycarbonyl, C₃₋₂₀ alkenyloxycarbonyl, C₈₋₂₀ aralkyloxycarbonyl, C₇₋₂₀ aryloxycarbonyl, C₂₋₂₀ alkylcarbonyloxy, C₃₋₂₀ alkenylcarbonyloxy, C₈₋₂₀ aralkylcarbonyloxy, C₇₋₂₀ arylcarbonyloxy, C₁₄₋₂₀ aralkyloxyaralkyl, C₁₋₂₀ alkylthio, C₇₋₂₀ aralkylthio, C₆₋₂₀ arylthio, nitro, formyl, hydroxyl and/or cyano groups and/or one or more halogen atoms.

The aryl groups contained in these substituents may be substituted further by one or more ₁₋₆ alkyl, C₁₋₆ alkoxy, C₇₋₁₀ aralkyl, C₇₋₁₀ aralkyloxy and/or hydroxyl groups and/or one or more halogen atoms.

Specific examples of R₂ and R₄ include methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, secbutyl, tert-butyl, n-pentyl, isopentyl, n-hexyl, 2-ethylhexyl, n-octyl, n-nonyl, n-decyl, n-undecyl, n-dodecyl, n-tridecyl, n-tetradecyl, n-pentadecyl, n-hexadecyl, n-heptadecyl, n-octadecyl, cyclopentyl, cyclohexyl, 4-methylcyclohexyl, 2,5-dimethylcyclohexyl, 2,6-dimethylcyclohexyl, 3,4-dimethylcyclohexyl, 3,5-dimethylcyclohexyl, 3,3,5-trimethylcyclohexyl, 4-tertbutylcyclohexyl, cycloheptyl, cyclooctyl, cyclohexylmethyl, 2-cyclohexylethyl, bornyl, isobornyl, 2-norbornanemethyl, 1-adamantylmethyl, vinyl, allyl, 3-butenyl, 2-hexenyl, 3-hexenyl, 4-hexenyl, 5-hexenyl, 2-heptenyl, 6-nonenyl, 1-cyclohexenyl, cinnamyl, 2-methoxyethyl, 2-ethoxyethyl, 2-isopropoxyethyl, 2-n-butoxyethyl, 2-n-hexyloxyethyl, 3-methoxypropyl, 3-ethoxypropyl, 3-n-propoxypropyl, 3-n-butoxypropyl, 3-n-hexyloxypropyl, 3-cyclohexyloxypropyl, 2-methoxyethoxyethyl, 2-ethoxyethoxyethyl, 2-allyloxyethyl, 2-benzyloxyethyl, 2-phenethyloxyethyl, 2-(4'-methylbenzyloxy)ethyl, 2-(4'-chlorobenzyloxy)ethyl, 2-benzyloxymethoxyethyl, 2-phenoxyethyl, 2-(4'-chlorophenoxy)ethyl, 2-(4'-methylphenoxy)ethyl, 2-(4'-methoxyphenoxy)ethyl, 2-phenoxyethoxyethyl, 2-tetrahydrofurfuryl, 2 chloroethyl, 3-ohloropropyl, 2,2,2-trichloroethyl, benzyl, α-methylbenzyl, α-ethylbenzyl, phenethyl, α-methylphenethyl, α,α-dimethylphenethyl, 4-(4'-methylphenethyl), 4-methylbenzyl, 3-methylbenzyl, 2-methylbenzyl, 4-isopropylbenzyl, 4-allylbenzyl, 4-benzylbenzyl, 4-phenethylbenzyl, 4-phenylbenzyl, 4-(4'-methylphenyl)benzyl, 4-methoxybenzyl, 4-n-butoxybenzyl, 3,4-dimethoxybenzyl, 4-methoxymethylbenzyl, 4-allyloxybenzyl, 4-vinyloxymethylbenzyl, 4-benzyloxybenzyl, 4-phenethyloxybenzyl, 4-phenoxybenzyl, 3-hydroxybenzyl, 2-hydroxybenzyl, 4-hydroxy-3-methoxybenzyl, 4-chlorobenzyl, 3-chlorobenzyl, 2-chlorobenzyl, 2-furfuryl, diphenylmethyl, phenyl, 1-naphthyl, 2-naphthyl, 3-furyl, 3-thienyl, 4-methylphenyl, 3-methylphenyl, 2-methylphenyl, 4-ethylphenyl, 3-ethylphenyl, 2-ethylphenyl, 4-n-propylphenyl, 4-isopropylphenyl, 4-n-butylphenyl, 4-sec-butylphenyl, 4-tert-butylphenyl, 4-n-pentylphenyl, 4-isopentylphenyl, 4-n-hexylphenyl, 4-n-octylphenyl, 4-tert-octylphenyl, 4-n-decylphenyl, 4-n-dodecylphenyl, 4-cyclopentylphenyl, 4-cyclohexylphenyl, 2-cyclohexylphenyl, 4-allylphenyl, 4-benzylphenyl, 2-benzylphenyl, 4-cumylphenyl, 4-(4'-methoxy-cumyl)phenyl, 4-(4'-chlorobenzyl)phenyl, 4-phenylphenyl, 3-phenylphenyl, 2-phenylphenyl, 4-(4'-methoxyphenyl)phenyl, 2-(2'-methoxyphenyl)phenyl, 4-(4'-chlorophenyl)phenyl, 4-methoxyphenyl, 3-methoxyphenyl, 2-methoxyphenyl, 4-ethoxyphenyl, 2-ethoxyphenyl, 4-isopropoxyphenyl, 4-n-butoxyphenyl, 4-n-hexyloxyphenyl, 4-n-octyloxyphenyl, 4-n-dodecyloxypehenyl, 4-cyclohexyloxyphenyl, 1-(2-methylnaphthyl), 1-(4-methoxynaphthyl), 1-(4-n-butoxynaphthyl), 1-(5-ethoxynaphtyl), 2-(6-ethoxynaphthyl), 2-(6-n-hexyloxynaphthyl), 2-(7-methoxynaphthyl), 2-(7-n-butoxynaphthyl), 4-methoxymethylphenyl, 4-ethoxymethylphenyl, 4-n-butoxymethylphenyl, 3-methoxymethylphenyl, 4-(2'-methoxyethyl)phenyl, 4-(2'-ethoxyethyloxy)phenyl, 4-(2'-n-butoxyethyloxy)phenyl, 4-vinyloxyphenyl, 4-allyloxyphenyl, 4-(5'-pentenyloxy)phenyl, 1-(4-allyloxynaphthyl), 4-allyloxymethylphenyl, 4-(2'-allyloxyethyloxy)phenyl, 4-benzyloxyphenyl, 2-benzyloxyphenyl, 4-phenethyloxyphenyl, 4-(4'-chlorobenzyloxy)phenyl, 4-(4'-methylbenzyloxy)phenyl, 4-(4'-methoxybenzyloxy)phenyl, 1-(4-benzyloxy)naphthyl, 2-(6-benzyloxynaphthyl), 2-(7-benzyloxynaphthyl), 4-(benzyloxymethyl)phenyl, 4-(2'-benzyloxyethyloxy)phenyl, 4-phenoxyphenyl, 3-phenoxyphenyl, 4-(4'-methylphenoxy)phenyl, 4-(4'-methoxyphenoxy)phenyl, 4-(4-chlorophenoxy)phenyl, 1-(4-phenoxynaphthyl), 4-phenoxymethylphenyl, 4-(2'-phenoxyethyloxy)phenyl, 4-[2'-(4'-methylphenyl)oxyethyloxy]-phenyl, 4-[2'-4'-methoxyphenyl)oxyethyloxy]phenyl, 4-[2'-(4'-chlorophenyl)oxyethyloxy]phenyl, 4-acetylphenyl, 2-acetylphenyl, 4-ethylcarbonylphenyl, 4-n-butylcarbonylphenyl, 4-n-hexylcarbonylphenyl, 4-n-octylcarbonylphenyl, 4-cyclohexylcarbonylphenyl, 1-(4-acetylnaphthyl), 4-allylcarbonylphenyl, 4-benzylcarbonylphenyl, 4-(4'-methylbenzyl)carbonylphenyl, 4-phenylcarbonylphenyl, 4-(4'-methylphenyl)carbonylphenyl, 4-(4'-chlorophenyl)carbonylphenyl, 1-(4-phenylcarbonylnaphthyl), 4-methoxycarbonylphenyl, 4-ethoxycarbonylphenyl, 4-n-propoxycarbonylphenyl, 4-n-butoxycarbonylphenyl, 4 -n-hexyloxycarbonylphenyl, 4-n-decyloxycarbonylphenyl, 4-cyclohexyloxycarbonyphenyl, 1-(4-ethoxycarbonynaphthyl), 2-(6-methoxycarbonylnaphthyl), 2-(6-n-butoxycarbonylnaphthyl), 4-allyloxycarbonylphenyl, 4-benzyloxycarbonylphenyl, 4-phenethyloxycarbonylphenyl, 2-(6-benzyloxycarbonylnaphthyl), 4-phenyloxycarbonylphenyl, 4-(4'-ethylphenyl)oxycarbonylphenyl, 4-(4'-chlorophenyl)oxycarbonylphenyl, 2-(6-phenyloxycarbonylnaphthyl), 4-acetyloxyphenyl, 4-ethylcarbonyloxyphenyl, 4-n-propylcarbonyloxyphenyl, 4-n-pentylcarbonyloxyphenyl, 4-n-octylcarbonyloxyphenyl, 4-cyclohexylcarbonyloxyphenyl, 1-(4-acetyloxynaphthyl), 1-(5-acetyloxynaphthyl), 2-(6-ethylcarbonyloxynaphthyl), 4-allylcarbonyloxyphenyl, 4-benzylcarbonyloxyphenyl, 4-phenethylcarbonyloxyphenyl, 2-(6-benzylcarbonyloxynaphthyl), 4-phenylcarbonyloxyphenyl, 4-(4'-methylphenyl)carbonyloxyphenyl, 4-(2'-methylphenyl)carbonyloxyphenyl, 4-(4'-chlorophenyl)carbonyloxyphenyl, 4-(2'-chlorophenyl)carbonyloxyphenyl, 1-(4-phenylcarbonyloxynaphthyl), 2-(6-phenylcarbonyloxynaphthyl), 4-(4'-benzyloxy)cumylphenyl, 4-methylthiophenyl, 4-ethylthiophenyl, 4-n-butylthiophenyl, 4-n-hexylthiophenyl, 4-cyclohexylthiophenyl, 4-benzylthiophenyl, 4-(4'-chlorobenzylthio)phenyl, 4-phenylthiophenyl, 4-(4'-methylphenylthio)phenyl, 4-(4'-methoxyphenylthio)phenyl, 4-(4'-chlorophenylthio)phenyl, 1-(4-methylthionaphthyl), 2-(6-ethylthionaphthyl), 2-(6-phenylthionaphthyl), 4-fluorophenyl, 3-fluorophenyl, 2-fluorophenyl, 4-chlorophenyl, 3-chlorophenyl 2,-chlorophenyl, 4-bromophenyl, 1-(4-chloronaphthyl), 2-(4-chloronaphthyl), 2-(6-bromonaphthyl), 4-nitrophenyl, 3-nitrophenyl, 4-formylphenyl, 3-formylphenyl, 2-formylphenyl, 4-hydroxyphenyl, 3-hydroxyphenyl 2-hydroxyphenyl, 4-cyanophenyl, 2-cyanophenyl, 2-chloro-4-nitrophenyl, 4-chloro-2-nitrophenyl, 6-chloro-3-methylphenyl, 2-chloro-6-methylphenyl, 4-chloro-2-methylphenyl, 4-chloro-3-methylphenyl, 2,4-dimethylphenyl, 2,5-dimethylphenyl, 3,4-dimethylphenyl, 3,5-dimethylphenyl, 2,6-dimethylphenyl, 2,3,5-trimethylphenyl, 2,3,6-trimethylphenyl, 2,4,6-trimethylphenyl, 2,3-dichlorophenyl, 2,4-dichlorophenyl, 2,5-dichlorophenyl, 2,6-dichlorophenyl, 3,4-dichlorophenyl, 3,5-dichlorophenyl, 2,4,6-trichlorophenyl, 2-methoxy-4-methylphenyl, 2,6-dimethoxyphenyl, 3,5-dimethoxyphenyl, 3,5-diethoxyphenyl, 3,5-di-n-butoxyphenyl, 3,4,5-trimethoxyphenyl, and 1-(2,4-dichloronaphthyl).

X₁, X₂, Y₁ and Y₂ individually represent an oxygen atom or a sulfur atom.

In the formulae (i) and (ii), the ring A and ring A' individually represent a benzene ring or naphthalene ring while the ring D indicates a naphthalene ring. More preferably, the ring A and ring A' are each a benzene ring.

In the formulae (i) and (ii), p, q and r individually represent an integer of 1-4. When p, q and r individually represent an integer of 2 or greater, R₅, R₆ and R₇ may be either the same or different. Namely, when p (q or r) is 2, for example, two R₅ s (R₆ s or R₇ s) may be the same alkyl group or different alkyl groups, or may be an alkyl group and a halogen atom, respectively.

In the formulae (i) and (ii), R₅, R₆ and R₇ individually represent a hydrogen or halogen atom or an alkyl, alkoxy, aralkyl, aryl or hydroxyl group; preferably a hydrogen, fluorine, chlorine or bromine atom or a C₁₋₂₀ alkyl, C₅₋₁₄ cycloalkyl, C₁₋₂₀ alkoxy, C₇₋₂₀ aralkyl, phenyl or hydroxyl group; more preferably a hydrogen, fluorine or chlorine atom or a C₁₋₄ alkyl, cyclohexyl, C₁₋₄ alkoxy, benzyl, phenyl or hydroxyl group, with a hydrogen atom being particularly preferred.

In the formula (i), --B-- represents a group containing at least one group selected from the class consisting of --R₈ CR₉ -- (in which R₈ and R₉ individually represent a hydrogen atom or an alkyl, trifluoromethyl or aryl group or are combined together to form a ring), --O--, --S--, a phenylene group, --CO--, a single bond, C_(m) H_(2m) --, m standing for an integer of 2-10, --CR₁₀ ═CR₁₁ -- (in which R₁₀ and R₁₁ are individually a hydrogen atom or an alkyl or aryl group), --SO--, and --SO₂ --.

R₈ and R₉ individually represent a hydrogen atom or an alkyl, trifluoromethyl or aryl group or are combined together to form a ring, preferably a hydrogen atom, a C₁₋₂₀ alkyl, trifluoromethyl or phenyl group or a C₅₋₁₄ cycloalkane ring formed of R₈ and R₉ ; more preferably a hydrogen atom, a C₁₋₄ alkyl, trifluoromethyl or phenyl group, or a cyclopentane, cyclohexane, cycloheptane or cyclooctane ring formed of R₈ and R₉.

m stands for an integer of 2-10, with an integer of 2-6 being more preferred.

R₁₀ and R₁₁ individually represent a hydrogen atom or an alkyl or aryl group, preferably a hydrogen atom or a C₁₋₂₀ alkyl or phenyl group, more preferably a hydrogen atom or a C₁₋₄ alkyl group.

In particular, --B-- is preferably a group containing at least one group selected from the class consisting of --R₈ CR₉ -- (in which R₈ and R₉ individually represent a hydrogen atom or an alkyl, trifluoromethyl or aryl group or are combined together to form a ring), --O--, --S--, a phenylene group, --CO--, and a single bond. Of these, --R₈ CR₉ (in which R₈ and R₉ individually represent a C₁₋₄ alkyl group), --O--, --S--, ##STR6## --OOC-- and single bond are preferred.

Specific example include --CH₂ --, --CH₃ CH--, --CH₃ CCH₃ --, --CH₃ CC₂ H₅ --, CH₃ CiBu--, ##STR7## 1,1-cyclopentylidene, 1,1-cyclohexylidene, 1,1-cycloheptylidene, 1,1-cyclooctylidene, --CF₃ CCF₃ --, --O--, --S--, 1,4-phenylene, ##STR8## --COO--, --OOC--, single bond, --CO--, --(CH₂)₂ --, --(CH₂)₃ --, --(CH₂)₄ --, --CH═CH--, --CCH₃ ═CCH₃ --, --CC₂ H₅ ═CC₂ H₅ --, --OCH₂ --, --CH₂ O--, --O(CH₂)₂ O--, --O(CH₂)₃ O--, --O(CH₂)₄ O--, --O(CH₂)₅ O--, --O(CH₂)₆ O--, --CH₂ CO--, --COCH₂ --, --CH₂ CH₂ CO--, --COCH₂ CO--, ##STR9## --COCH═CH--, --COOCH₂ CO--, and --COOCH₂ CH₂ OOC--.

In the formulae (1) and (2) of this invention, particularly preferred --Z₁ -- and --Z₂ -- are the groups represented by the following formulae (iii) to (ix), respectively: ##STR10## wherein R₅, R₆, R₇, R₈, R₉, p, q and r have the same meanings as defined above.

Among the compounds according to this invention, which are represented by the formula (1), the compounds represented by the formula (3) are novel compounds found by the present inventors.

In the compounds represented by the formula (3) according to this invention, the position of substitution by each phenolic hydroxyl group or carbamate group is preferably the ortho-, meta- or para-position, more preferably the meta- or para-position, both relative to --Z₃ --.

Of the compounds (3) according to the present invention, preferred examples include those represented by the following formula (3-a) to (3-i), respectively: ##STR11## wherein R₁, R₂, R₅, R₆, X₁, Y₁, p and q have the same meanings as defined above.

In the formulae (3-a) to (3-i), examples of R₁, R₂, R₅, R₆, X₁, Y₁, p and q are as described above. In particular, R₁ is preferably a hydrogen atom or a C₁₋₄ alkyl group, notably a hydrogen atom, R₅ and R₆ are preferably a hydrogen atom or a C₁₋₄ alkyl group, notably a hydrogen atom, and X₁ is preferably an oxygen atom.

In the formulas (3-a) to (3-i), --Z₃ -- represents a group containing at least one group selected from the class consisting of --R₈ CR₉ -- (in which R₈ and R₉ individually represent a hydrogen atom or an alkyl, trifluoromethyl or aryl group or are combined together to form a ring), --O--, --S--, a phenylene group, --CO--, --C_(m) H_(2m) -- (in which m stands for an integer of 2-10), --CR₁₀ ═CR₁₁ -- (in which R₁₀ and R₁₁ individually represent a hydrogen atom or an alkyl or aryl group), --SO--, and --SO₂ --.

In --Z₃ --, R₈ and R₉ may individually represent a hydrogen atom or an alkyl, trifluoromethyl or aryl group or may be combined together to form a ring; preferably a hydrogen atom, a C₁₋₂₀ alkyl, trifluoromethyl or phenyl group or a C₅₋₁₄ cycloalkane ring formed of R₈ and R₉ ; most preferably a hydrogen atom, a C₁₋₄ alkyl, trifluoromethyl or phenyl group, or a cycloheptane, cyclohexane or cyclopentane ring formed by R₈ and R₉. A methyl group is especially preferred. m stands for an integer of 2-10, more preferably an integer of 2-6. R₁₀ and R₁₁ individually represent a hydrogen atom or an alkyl or aryl group, preferably a hydrogen atom or a C₁₋₂₀ alkyl or phenyl group, more preferably a hydrogen atom or a C₁₋₄ alkyl group.

More preferred --Z₃ -- is a group containing at least one group selected from the class consisting of --R₈ CR₉ -- (in which R₈ and R₉ individually represent a hydrogen atom or an alkyl, trifluoromethyl or aryl group or are combined together to form a ring), --O--, --S--, 1,4-phenylene and --CO--. Particularly preferred is a group containing at least one group selected from the class consisting of --R₈ CR₉ -- (in which R₈ and R₉ individually represent a C₁₋₄ alkyl group), --O--, --S--, ##STR12## and --OOC--.

Among the compounds (3) according to the present invention, particularly preferred compounds are those represented by the following formulas (4) to (8), respectively: ##STR13## wherein R₈ and R₉ individually represent a C₁₋₄ alkyl group, and R₂, X₁ and Y₁ have the same meanings as defined above. ##STR14## wherein R₂, X₁ and Y₁ have the same meanings as defined above. ##STR15## wherein R₂, X₁ and Y₁ have the same meanings as defined above. ##STR16## wherein R₂, X₁ and Y₁ have the same meanings as defined above. ##STR17## wherein R₂, X₁ and Y₁ have the same meanings as defined above.

Among the compounds represented by the formula (4), the compounds represented by the formula (4-1) or (4-2) are particularly preferred. ##STR18## wherein R₂ and Y₁ have the same meanings as defined above.

Among the compounds represented by the formula (5), the compounds represented by the following formula (5-1) or 5-2) are particularly preferred. ##STR19## wherein R₂ and Y₁ have the same meanings as defined above.

Among the compounds represented by the formula (6), the compounds represented by the following formulae (6-1) are particularly preferred. ##STR20## wherein R₂ and Y₁ have the same meanings as defined above.

Among the compounds represented by the formula (7), the compounds represented by the following formula (7-1) or (7-2) are particularly preferred. ##STR21## wherein R₂ has the same meaning as defined above.

Among the compounds represented by the formula (8), the compounds represented by the following formula (8-1) are particularly preferred. ##STR22## wherein R₂ has the same meaning as defined above.

The phenol compounds represented by the formula (1), (2) or (3), said compounds pertaining to the present invention, can be prepared in a manner known per se in the art [for example, the process disclosed in Methoden Der Organischen Chemie, 8, 137(1952), Shin Jikken Kagaku Koza (New Textbook of Experimental Chemistry), 14, 1658,1836, Maruzen (1977), or Angewandte Chemie International Edition, 6, 281(1967)].

The compounds represented by the formula (1), which pertain to the present invention, can each be prepared typically from an aminophenol derivative, which is represented by the following formula (a): ##STR23## wherein R₁ and Z₁ have the same meanings as defined above, and a chloroformate ester, chlorothioformate ester or chlorodithioformate ester represented by the following formula (b): ##STR24##

wherein R₂, X₁ and Y₁ have the same meanings as defined above.

The compounds represented by the formula (2), which relate to the present invention, can each be prepared typically from a phenol derivative, which is represented by the following formula (c);

    HO--Z.sub.2 --Y.sub.2 --H                                  (c)

wherein Y₂ and Z₂ have the same meanings as defined above, and from an isocyanate or thioisocyanate derivative, which is represented by the following formula (d):

    X.sub.2 ═C═N--R.sub.4                              (d)

wherein R₄ and X₂ have the same meanings as defined above, or a chloroformic amide derivative represented by the following formula (e): ##STR25## wherein R₃, R₄ and X₂ have the same meanings as defined above.

The novel phenol compounds represented by the formula (3), which also relate to the present invention, can each be prepared typically from an aminophenol derivative, which is represented by the following formula (aa): ##STR26## wherein R₁, R₅, R₆, Z₃, p and q have the same meanings as defined above, and a chloroformate ester, chlorothioformate ester or chlorodithioformate ester represented by the above formula (b).

The aminophenol derivative useful as a raw material upon preparation of the novel phenol compound (3) of the present invention can be prepared in a manner known per se in the art.

For example, an aminophenol derivative, which is represented by the following formula (4-a): ##STR27## wherein R₁, R₅, R₆, R₈, R₉, p and q have the same meanings as defined above, can be prepared in a manner known per se in the art, for example, in accordance with the process disclosed in Journal of American Chemical Society, 68, 2600 (1946), British Patent 1,028,156, Japanese Patent Laid-Open No. 114942/1987, 116546/1987 or 172364/1989, or the like, namely, by decomposing the diazonium salt of a corresponding dianilinoalkane, by reacting a corresponding diphenol alkane with a corresponding aniline, by reacting a corresponding monoalkenylaniline with a corresponding phenol in the presence of a catalyst, or by reacting a corresponding monoalkenylphenol and a corresponding aniline in the presence of a catalyst.

Further, aminophenol derivatives represented by the following formula (5-a): ##STR28## wherein R₁, R₅, R₆, p and q have the same meanings as defined above can each be prepared in a manner known per se in the art, for example, in accordance with the process disclosed in Pharmaceutical Bulletin, 5, 397 (1952), Journal of the Society of Synthetic Organic Chemistry, Japan, 24, 44 (1966), U.S. Pat. No. 3,240,706 or the like, namely, by, for example, reacting a nitrochlorobenzene with a dihydroxybenzene in the presence of a base and then reducing the resultant nitrophenoxyphenol.

Aminophenol derivatives represented by the following formula (6-a): ##STR29## wherein R₁, R₅, R₆, p and q have the same meanings as defined above can each be prepared in a manner known per se in the art, for example, in accordance with the process disclosed in Indian Journal of Chemistry, 15B, 661 (1977), U.S. Pat. No. 3,443,943 or the like, namely, by reacting a nitrochlorobenzene with a hydroxythiophenol in the presence of a base and then reducing the resultant hydroxyphenyl-nitrophenyl sulfide.

In addition, aminophenol derivatives represented by the following formula (7-a): ##STR30## wherein R₁, R₅, R₆, p and q have the same meaning as defined above can each be prepared in a manner known per se in the art, for example, in accordance with the process disclosed in Japanese Patent Laid-Open No. 4441/1974 or the like, namely, by reacting a hydroxybiphenylcarboxylic acid with a nitrophenol in the presence of a catalyst and then reducing the resultant nitrophenyl hydroxybiphenylcarboxylate.

Aminophenol derivatives represented by the following formula (8-a): ##STR31## wherein R₁, R₅, R₆, p and q have the same meanings as defined above can each be prepared in a manner known per se in the art, for example, in accordance with the process disclosed in Journal of Organic Chemistry, 37, 1425 (1972), Journal of Organic Chemistry, 38, 3160 (1973) or the like, namely, by reacting a dihydroxybenzene with a nitrobenzoic acid and then reducing the resultant hydroxyphenyl nitrobenzoate.

Furthermore, the compounds represented by the formula (b) can each be prepared in a manner known per se in the art, for example, in accordance with the process disclosed in Methoden Der Organischen Chemie, 8, 101 (1952), Journal of American Chemical Society, 72, 1254 (1950), Angewandte Chemie International Edition, 4, 281 (1967), Chemical Review, 73, 75 1973) or the like, namely, by the reaction between phosgene or thiophosgene and an alcohol, phenol, thiol or thiophenol.

Upon production of the phenol compound (3) of the present invention, a conventional reaction process can be employed for the reaction between the aminophenol derivative represented by the formula (aa) and the compound represented by the formula (b). For example, they can be reacted by adding the compound (b) dropwise to the compound (aa) under stirring. Upon conducting the reaction, the molar ratio of the compound (aa) to the compound (b) is generally in a range of about 1 to about 0.5-2, preferably in a range of about 1 to about 0.8-1.5, more preferably in a range of about 1 to about 0.8-1.2.

Although the reaction may be conducted in a solventless manner, it is generally more preferable to carry it out using a solvent.

Examples of solvents usable in the reaction include hydrocarbon solvents such as hexane, octane, benzene, toluene and xylene; ketone solvents such as acetone, methyl ethyl ketone, methyl isobutyl ketone and cyclohexanone; ester solvents such as ethyl acetate, butyl acetate and amyl acetate; ether solvents such as diethyl ether, diisopropyl ether, dibutyl ether, tetrahydrofuran and dioxane; halogenated solvents such as dichloromethane, chloroform, carbon tetrachloride, 1,2-dichloroethane, Perclene, chlorobenzene and dichlorobenzene; and mixed solvents thereof. The reaction can also be conducted in the presence of both one of the solvents or mixed solvents and water.

The reaction temperature generally range from 0° C. to 200° C., with about 0°-100° C. being preferred. The reaction time is generally in a range of from several minutes to several tens hours although it varies significantly depending on reaction conditions such as reaction temperature.

During the reaction, hydrogen chloride is by-produced. Use of a dehydrochlorinating agent, for example, an organic base such as dimethylaniline or an inorganic base such as sodium hydrogencarbonate, sodium carbonate, potassium hydrogencarbonate or potassium carbonate is preferred. It is particularly preferred to use an inorganic base. When such an inorganic base is employed, the inorganic base can be used as an aqueous solution without any problems.

After the completion of the reaction, the phenol compound (3) of the present invention can be isolated by collecting the reaction product in a manner known per se in the art and then purifying it in accordance with a conventional procedure, for example, recrystallization or column chromatography.

Among the compounds (1) of the present invention, those of the formula (1) in which --Z₁ -- is represented, for example, by the formula (viii) can be prepared in a manner known per se in the art, for example, in accordance with the process disclosed in Chemical and Pharmaceutical Bulletin, 26, 2508 (1978).

Among the compounds (1) of the present invention, those of the formula (1) in which --Z₁ -- is represented, for example, by the formula (ix) can be prepared in a manner known per se in the art, for example, in accordance with the process disclosed in Synthesis, 277 (1979).

Among the compounds (2) of the present invention, those of the formula (2) in which --Z₂ -- is represented, for example, by the formula (iii) can be prepared in a manner known per se in the art, for example, in accordance with the process disclosed in Collection of Czechoslovak Chemical Communication, 42, 1651 (1977) or U.S. Pat. No. 3,632,631.

Among the compounds (2) of the present invention, those of the formula (2) in which --Z₂ -- is represented, for example, by the formula (iv) or (v) can be prepared in a manner known per se in the art, for example, in accordance with the process disclosed in U.S. Pat. No. 3,371,109.

Among the compounds (2) of the present invention, those of the formula (2) in which --Z₂ -- is represented, for example, by the formula (viii) can be prepared in a manner known per se in the art, for example, in accordance with the process disclosed in U.S. Pat. No. 3,632,631.

Among the compounds (2) of the present invention, those of the formula (2) in which --Z₂ -- is represented, for example, by the formula (ix) can be prepared in a manner known per se in the art, for example, in accordance with the process disclosed in Journal of Agricultural and Food Chemistry, 13, 537 (1965), 14, 555 (1966), 16, 561 (1968) or 19, 432,441 (1971).

The heat-sensitive recording material according to the present invention features the inclusion of at least one compound represented by the formula (1) or (2) in a heat-sensitive recording material which contains an electron-donating chromogenic compound and an electron-attracting compound. Describing in more detail the constitution of the heat-sensitive recording material of this invention, it is a heat sensitive recording material which contains an electron-donating chromogenic compound and, as an electron attracting compound, at least one compound represented by the formula (1) or (2), or a heat-sensitive recording material which contains an electron-donating chromogenic compound, an electron-attracting compound and at least one compound represented by the formula (1) or (2).

As will be described later, these heat-sensitive recording materials additionally contain various known additives which have been used to produce conventional heat-sensitive materials, for example, a thermofusible compound.

Each compound represented by the formula (1) or (2), which pertains to the present invention, features the inclusion of a phenolic hydroxyl group and a carbamate group in its molecule. The present invention relates to a heat-sensitive recording material containing an electron-donating chromogenic compound and an electron-attracting compound, in which one or more of the compounds represented by the formula (1) or (2) are contained as the electron-attracting compound. The heat-sensitive recording material of this invention has very strong color-producing ability and provides a color image with excellent storage stability (hydrothermoresistance, waterproofness, etc.). Among the compounds represented by the formula (1) or (2) and useful in the heat-sensitive recording material according to this invention, those having a melting point not lower than about 60° C. are preferred. By using as an electron-attracting compound a compound--whose melting point is about 60° C. to 150° C., preferably about 80° C. to 130° C.--out of the compounds represented by the formula (1) or (2), it is possible to provide a heat-sensitive recording material which is not only excellent in the storage stability of a color image to be produced but also good in color-producing sensitivity.

Further, a compound which is represented by the formula (1) or (2) and has a melting point of 150° C. or higher can also provide a heat-sensitive recording material not only excellent in the storage stability of a color image to be produced but also good in color-producing sensitivity, provided that another electron-attracting compound and/or a thermofusible compound having a melting point of about 60° C. to 150° C., said thermofusible compound being to be described subsequently, is used in combination.

As a compound containing a phenolic hydroxyl group and a carbamate group in its molecule, 3-ethoxycarbonylaminophenol, 4-phenyloxycarbonylaminophenol or the like can be mentioned. As a result of a study conducted by the present inventors, it has, however, been found that a heat-sensitive recording material using the above compound, which contains only one benzene ring in its molecule, as an electron-attracting compound or a heat-sensitive recording material using, as an electron-attracting compound, the above compound in combination with another known electron-attracting compound is hardly considered to be good in the storage stability of a color image to be produced.

Japanese Patent Publication No. 59796/1990 proposed heat-sensitive recording materials which use, as an electron-attracting compound (color-developing agent), a blocked phenol compound obtained by the reaction of an isocyanate compound and a phenol compound. The blocked phenol compounds disclosed in the above patent publication are, however, compounds which do not contain any hydroxyl group in their molecules. Accordingly, heat-sensitive recording materials containing as electron-attracting compounds these blocked phenol compounds, for example, 4-tert-butylphenyloxycarbonylaminobenzene or 2,4-bis(4'-tert-butylphenyloxycarbonylamino)toluene have very poor color-producing ability and cannot produce any color even when heated at high temperatures, for example, at 150° C. These blocked phenol compounds are therefore not considered to have any practical function as an electron-attracting compound. From the foregoing, it is unique and also surprising that the heat-sensitive recording material according to this invention, which contains as an electron-attracting compound at least one compound represented by the formula (1) or (2), is excellent in the storage stability of a color image to be produced.

Further, Japanese Patent Laid-Open No. 18084/1990 proposes, as thermofusible compounds (sensitizers) for heat-sensitive recording materials, carbamate compounds having one of several specific structures. The carbamate compounds disclosed in the above patent publication are considerably different from the compounds of the formula (1) or (2), the latter compounds pertaining to the present invention, in that the former compounds do not contain any phenolic hydroxyl group in their molecules. Because of this, heat-sensitive recording materials containing as a sensitizer one of the compounds disclosed in the above patent publication, for example, 1,6-bis(phenyloxycarbonylamino)hexane are very poor in the storage stability (for example, heat resistance, hydrothermoresistance and waterproofness) of a color image to be produced, compared with heat-sensitive recording materials according to the present invention, the latter heat-sensitive recording materials containing an electron-donating chromogenic compound, an electron-attracting compound (for example, bisphenol A) and a compound of the formula (1) or (2). As has been described above, the excellent storage stability of a color image produced o the heat-sensitive recording material according to the present invention cannot be inferred from any conventional compounds or conventional technology and, although the mechanism has not been fully elucidated, is believed to be attributed to certain advantageous effects inherent to the compound of the formula (1) or (2) which pertains to the present invention and contains both a phenolic hydroxyl group and a carbamate group in its molecule.

Specific examples of the compounds according to the present invention, which are represented by the formula (1) or (2), include, but are not limited to, the following compounds.

1. 2-(4'-Hydroxyphenyl)-2-(4"-methoxycarbonylaminophenyl)propane

2. 2-(4'-Hydroxyphenyl)-2-(4"-n-propoxycarbonylaminophenyl)propane

3. 2-(4'-Hydroxyphenyl)-2-(4"-n-butoxycarbonylaminophenyl)propane

4. 2-(4'-Hydroxyphenyl)-2-(4"-n-decyloxycarbonylaminophenyl)propane

5. 2-(4'-Hydroxyphenyl)-2-(4"-n-hexadecyloxycarbonylaminophenyl)propane

6. 2-(4'-Hydroxyphenyl)-2-(4"-cyclohexyloxycarbonylaminophenyl)propane

7. 2-(4'-Hydroxyphenyl)-2-(4"-cyclohexylmethyloxycarbonylaminophenyl)propane

8. 2-(4'-Hydroxyphenyl)-2-[4"-(2-tetrahydrofurfuryl)oxycarbonylaminophenyl]propane

9. 2-(4'-Hydroxyphenyl)-2-[4"-(2-methoxyethyl)oxycarbonylaminophenyl]propane

10. 2-(4'-Hydroxyphenyl)-2-[4"-(2-n-butoxyethyl)oxycarbonylaminophenyl]propane

11. 2-(4'-Hydroxyphenyl)-2-[4"-(3-ethoxypropyl)oxycarbonylaminophenyl]propane

12. 2-(4'-Hydroxyphenyl)-2-[4"-(3-n-hexyloxypropyl)oxycarbonylaminophenyl]propane

13. 2-(4'-Hydroxyphenyl)-2-[4"-(2-methoxyethoxyethyl)oxycarbonylaminophenyl]propane

14. 2-(4'-Hydroxyphenyl)-2-[4"-(2-phenoxyethyl)oxycarbonylaminophenyl]propane

15. 2-(4'-Hydroxyphenyl)-2-{4"-[2-(4-chlorophenoxy)ethyl]oxycarbonylaminophenyl}propane

16. 2-(4'-Hydroxyphenyl)-2-[4"-(3-chloropropyl)oxycarbonylaminophenyl]propane

17. 2-(4'-Hydroxyphenyl)-2-(4"-allyloxycarbonylaminophenyl)propane

18. 2-(4'-Hydroxyphenyl)-2-(4"-benzyloxycarbonylaminophenyl)propane

19. 2-(4'-Hydroxyphenyl)-2-[4"-(4-methylbenzyl)oxycarbonylaminophenyl]propane

20. 2-(4'-Hydroxyphenyl)-2-[4"-(4-phenoxybenzyl)oxycarbonylaminophenyl]propane

21. 2-(4'-Hydroxyphenyl)-2-[4"-(4-chlorobenzyl)oxycarbonylaminophenyl]propane

22. 2-(4'-Hydroxyphenyl)-2-[4"-(3-hydroxybenzyl)oxycarbonylaminophenyl]propane

23. 2-(4'-Hydroxyphenyl)-2-[4"(2-phenylethyl)oxycarbonylaminophenyl]propane

24. 2-(4'-Hydroxyphenyl)-2-(4"-phenyloxycarbonylaminophenyl)propane

25. 2-(4'-Hydroxyphenyl)-2-[4"-(2-naphthyl)oxycarbonylaminophenyl]propane

26. 2-(4'-Hydroxyphenyl)-2-[4"-(4-phenylphenyl)oxycarbonylaminophenyl]propane

27. 2-(4'-Hydroxyphenyl)-2-[4"-(4-methylphenyl)oxycarbonylaminophenyl]propane

28. 2-(4'-Hydroxyphenyl)-2-[4"-(3-methylphenyl)oxycarbonylaminophenyl]propane

29. 2-(4'-Hydroxyphenyl)-2-[4"-(4-cyclohexylphenyl)oxycarbonylaminophenyl]propane

30. 2-(4'-Hydroxyphenyl)-2-[4'-(4-cumylphenyl)oxycarbonylaminophenyl]propane

31. 2-(4'-Hydroxyphenyl)-2-[4"-(4-methoxyphenyl)oxycarbonylaminophenyl]propane

32. 2-(4'-Hydroxyphenyl)-2-[4"-(4-phenoxyphenyl)oxycarbonylaminophenyl]propane

33. 2-(4'-Hydroxyphenyl)-2-[4"-(4-chlorophenyl)oxycarbonylaminophenyl]propane

34. 2-(4'-Hydroxyphenyl)-2-[4"-(2-chlorophenyl)oxycarbonylaminophenyl]propane

35. 2-(4'-Hydroxyphenyl)-2-[4"-(4-nitrophenyl)oxycarbonylaminophenyl]propane

36. 2-(4'-Hydroxyphenyl)-2-[4"-(4-acetylphenyl)oxycarbonylaminophenyl]propane

37. 2-(4'-Hydroxyphenyl)-2-[4"-(4-ethoxycarbonylphenyl)oxycarbonylaminophenyl]propane

38. 2-(4'-Hydroxyphenyl)-2-[4"-(4-benzyloxyphenyl)oxycarbonylaminophenyl]propane

39. 2-(4'-Hydroxyphenyl)-2-[4"-(4-phenylcarbonylphenyl)oxycarbonylaminophenyl]propane

40. 2-(4'-Hydroxyphenyl)-2-[4"-(2-chloro-4-nitrophenyl)oxycarbonylaminophenyl]propane

41. 2-(4'-Hydroxyphenyl)-2-[4"-(2,4-dimethylphenyl)oxycarbonylaminophenyl]propane

42. 2-(3'-Methyl-4'-hydroxyphenyl)-2-(4"-ethoxycarbonylaminophenyl)propane

43. 2-(3'-Methyl-4'-hydroxyphenyl)-2-[4"-(4-methoxybenzyl)oxycarbonylaminophenyl]propane

44. 2-(3'-Ethyl-4'-hydroxyphenyl)-2-[4"-(4-tertbutylphenyl)oxycarbonylaminophenyl]propane

45. 2-(3',5'-Dimethyl-4'-hydroxyphenyl)-2-[4"-(2-methylphenyl)oxycarbonylaminophenyl]propane

46. 2-(3'-Methyl-4'-hydroxyphenyl)-2-(3"-methyl-4"-isobutoxycarbonylaminophenyl)propane

47. 2-(4'-Hydroxyphenyl)-2-[3"-methyl-4"-(4-allylphenyl)oxycarbonylaminophenyl]propane

48. 2-(4'-Hydroxyphenyl)-2-[3"-chloro-4"-(3-methoxyphenyl)oxycarbonylaminophenyl]propane

49. 2-(4'-Hydroxyphenyl)-2-[3",5"-dimethyl-4"-(4-tert-butylcyclohexyl)oxycarbonylaminophenyl]propane

50. 1-(4'-Hydroxyphenyl)-1-(4"-phenyloxycarbonylaminophenyl)cyclopentane

51. 1-(4'-Hydroxyphenyl)-1-[4"-(4-methylcyclohexyl)oxycarbonylaminophenyl]cyclohexane

52. 1-(4'-Hydroxyphenyl)-1-(4"-isopropoxycarbonylaminophenyl)cycloheptane

53. 1-(4'-Hydroxyphenyl)-1-[4"-(2-acetylphenyl)oxycarbonylaminophenyl]cyclooctane

54. 1-(4'-Hydroxyphenyl)-1-(4"-sec-butoxycarbonylaminophenyl)methane

55. 1-(4'-Hydroxyphenyl)-1-[4"-(1-naphtyl)oxycarbonylaminophenyl]methane

56. 2-(4'-Hydroxyphenyl)-2-(4"-tert-butoxycarbonylaminophenyl)butane

57. 2-(4'-Hydroxyphenyl)-2-[4"-(3-furyl)oxycarbonylaminophenyl]isohexane

58. 1-(4'-Hydroxyphenyl)-1-(4"-n-pentyloxycarbonylaminophenyl)-1-phenylmethane

59. 1-(4'-Hydroxyphenyl)-1-[4"-(3-thienyl)oxycarbonylaminophenyl]-1-phenylethane

60. 2-(4'-Hydroxyphenyl)-2-(4"-phenyloxycarbonylaminophenyl)hexafluoropropane

61. 2-(4'-Hydroxyphenyl)-2-(4"-N-phenyloxycarbonyl-N-methylaminophenyl)propane

62. 2-(4'-Hydroxyphenyl)-2-(4"-phenylthiolcarbonylaminophenyl)propane

63. 2-(4'-Hydroxyphenyl)-2-(4"-phenyloxythiocarbonylaminophenyl)propane

64. 2-(4'-Hydroxyphenyl)-2-(4"-ethoxycarbonylamino-1"-naphtyl)propane

65. 2-(3'-Hydroxyphenyl)-2-(4"-methoxycarbonylaminophenyl)propane

66. 2-(3"-Hydroxyphenyl)-2-(4"-n-butoxycarbonylaminophenyl)propane

67. 2-(3'-Hydroxyphenyl)-2-[4"-(2-phenoxyethoxyethyl)oxycarbonylaminophenyl]propane

68. 2-(3'-Hydroxyphenyl)-2-[4"-benzyloxycarbonylaminophenyl)propane

69. 2-(3'-Hydroxyphenyl)-2-[4"-(4-chlorobenzyl)oxycarbonylaminophenyl]propane

70. 2-(3'-Hydroxyphenyl)-2-(4"-phenyloxycarbonylaminophenyl)propane

71. 2-(3'-Hydroxyphenyl)-2-[4"-(1-naphtyl)oxyoarbonylaminophenyl]propane

72. 2-(3'-Hydroxyphenyl)-2-[4"-(2-phenylphenyl)oxycarbonylaminophenyl]propane

73. 2-(3'-Hydroxyphenyl)-2-[4"-(2-methylphenyl)oxycarbonylaminophenyl]propane

74. 2-(3'-Hydroxyphenyl)-2-[4"-(2-cyclohexylphenyl)oxycarbonylaminophenyl]propane

75. 2-(3'-Hydroxyphenyl)-2-[4"-(2-ethoxyphenyl)oxycarbonylaminophenyl]propane

76. 2-(3'-Hydroxyphenyl)-2-[4"-(3-phenoxyphenyl)oxycarbonylaminophenyl]propane

77. 2-(3'-Hydroxyphenyl)-2-[4"-(4-chlorophenyl)oxycarbonylaminophenyl]propane

78. 2-(3'-Hydroxyphenyl)-2-[4"-(2-chlorophenyl)oxycarbonylaminophenyl]propane

79. 2-(3'-Hydroxyphenyl)-2-[4"-(4-bromophenyl)oxycarbonylaminophenyl]propane

80. 2-(3'-Hydroxyphenyl)-2-[4"-(4-benzyloxyphenyl)oxycarbonylaminophenyl]propane

81. 2-(3'-Hydroxyphenyl)-2-[4"-(4-cumylphenyl)oxycarbonylaminophenyl]propane

82. 2-(3'-Hydroxyphenyl)-2-[4"-(2,4-dimethylphenyl)oxycarbonylaminophenyl]propane

83. 2-(3'-Hydroxyphenyl)-2-(3",5"-dimethyl-4"-phenyloxycarbonylaminophenyl)propane

84. 1-(3'-Hydroxyphenyl)-1-(4"-isopentyloxycarbonylaminophenyl)cyclohexane

85. 1-(3'-Hydroxyphenyl)-1-[4"-(2-acetylphenyl)oxycarbonylaminophenyl]cyclohexane

86. 1-(3'-Hydroxyphenyl)-1-[4"-(4-acetyloxyphenyl)oxycarbonylaminophenyl]methane

87. 2-(3'-Hydroxyphenyl)-2-(4"-phenyloxycarbonylaminophenyl)butane

88. 2-(3'-Hydroxyphenyl)-2-(4"-methoxycarbonylaminophenyl)isohexane

89. 1-(4'-methyl-3'-hydroxyphenyl)-1-(4"-methyl-3"-phenyloxycarbonylaminophenyl)methane

90. 1-(4'-methyl-3'-hydroxyphenyl)-1-[4"-methyl-3"-(4-chlorophenyl)oxyoarbonylaminophenyl]methane

91. 2-(4'-Hydroxyphenyl)-2-(3"-n-propoxycarbonylaminophenyl)propane

92. 2-(4'-Hydroxyphenyl)-2-[3"-(4-methylcyclohexyl)oxycarbonylaminophenyl]propane

93. 2-(4'-Hydroxyphenyl)-2-[3"-(2-cyclohexylethyl)oxycarbonylaminophenyl]propane

94. 2-(4'-Hydroxyphenyl)-2-[3"-(2-ethoxyethyl)oxycarbonylaminophenyl]propane

95. 2-(4'-Hydroxyphenyl)-2-[3"-(2-isopropoxyethyl)oxycarbonylaminophenyl]propane

96. 2-(4'-Hydroxyphenyl)-2-(3"-phenyloxycarbonylaminophenyl)propane

97. 2-(4'-Hydroxyphenyl) 2-[3"-(4-ethylphenyl)oxycarbonylaminophenyl]propane

98. 2-(4'-Hydroxyphenyl)-2-[3"-(4-methoxyphenyl)oxycarbonylaminophenyl]propane

99. 2-(4'-Hydroxyphenyl)-2-[3"-(2-fluorophenyl)oxycarbonylaminophenyl]propane

100. 2-(4'-Hydroxyphenyl)-2-[3"-(2-ethylphenyl)oxycarbonylaminophenyl]propane

101. 1-(4'-Hydroxyphenyl)-1-(3"-ethoxycarbonylaminophenyl)cyclohexane

102. 1-(4'-Hydroxyphenyl)-1-(3"-phenyloxycarbonylaminophenyl)cyclohexane

103. 2-(4'-Hydroxyphenyl)-2-[3"-(4-benzylphenyl)oxycarbonylaminophenyl]isohexane

104. 1-(2'-Hydroxyphenyl)-1-(4"-n-propoxycarbonylaminophenyl)methane

105. 1-(2'-Hydroxyphenyl)-1-(4"-cyclohexyloxycarbonylaminophenyl)methane

106. 1-(2'-Hydroxyphenyl)-1-(4"-benzyloxycarbonylaminophenyl)methane

107. 1-(2'-Hydroxyphenyl)-1-[4"-(2-methoxyphenyl)oxycarbonylaminophenyl]methane

108. 1-(4'-Hydroxyphenyl)-1-[2"-(4-methylphenyl)oxycarbonylaminophenyl]methane

109. 2-(4'-Hydroxyphenyl)-2-(4"-ethyl-2"-phenyloxycarbonylaminophenyl)propane

110. 1-(2'-Hydroxy-5'-methylphenyl)-1-(2"-hydroxy-3"-phenyloxycarbonylaminophenyl)methane

111. 1-(2',5'-Dihydroxyphenyl)-1-(3"-phenyloxycarbonylaminophenyl)methane

112. 1-(2',5'-Dihydroxyphenyl)-1-(4"-methyl-3"-methoxycarbonylaminophenyl)methane

113. 1-(2',5'-Dihydroxyphenyl)-1-(4"-methyl-3"-phenyloxycarbonylaminophenyl)methane

114. 1-(2'-Hydroxy-5'-n-butylphenyl)-1-(2"-benzyloxycarbonylaminophenyl)methane

115. 1-(2'-Hydroxy-5'-n-pentylphenyl)-1-(2"-phenyloxycarbonylaminophenyl)methane

116. 1-(2'-Hydroxy-5'-cumylphenyl)-1-(2"-methoxycarbonylaminophenyl)methane

117. 4-Hydroxyphenyl-4'-methoxycarbonylaminophenyl ether

118. 4-Hydroxyphenyl-4'-ethoxycarbonylaminophenyl ether

119. 4-Hydroxy-phenyl-4'-n-butoxycarbonylaminophenyl ether

120. 4-Hydroxyphenyl-4'-n-hexyloxycarbonylaminophenyl ether

121. 4-Hydroxyphenyl-4'-n-hexadecyloxycarbonylaminophenyl ether

122. 4-Hydroxyphenyl-4'-(2-methoxyethyl)oxycarbonylaminophenyl ether

123. 4-Hydroxyphenyl-4'-(3-methoxypropyl)oxycarbonylaminophenyl ether

124. 4-Hydroxyphenyl-4'-(2-allyloxyethyl)oxycarbonylaminophenyl ether

125. 4-Hydroxyphenyl-4'-benzyloxycarbonylaminophenyl ether

126. 4-Hydroxyphenyl-4'-phenyloxycarbonylaminophenyl ether

127. 4-Hydroxyphenyl-4'-(3-ethylphenyl)oxycarbonylaminophenyl ether

128. 4-Hydroxyphenyl-4'-(4-phenylphenyl)oxycarbonylaminophenyl ether

129. 4-Hydroxyphenyl-4'-(3-phenylphenyl)oxycarbonylaminophenyl ether

130. 4-Hydroxyphenyl-4'-(4-cyclopentylphenyl)oxycarbonylaminophenyl ether

131. 4-Hydroxyphenyl-4'-(3-chlorophenyl)oxycarbonylaminophenyl ether

132. 4-Hydroxyphenyl-4'-(2-benzyloxyphenyl)oxycarbonylaminophenyl ether

133. 4-Hydroxyphenyl-4'-(2,6-dimethylphenyl)oxycarbonylaminophenyl ether

134. 4-Hydroxyphenyl-4'-phenylthiolcarbonylaminophenyl ether

135. 4-Hydroxy-1-naphthyl-4'-ethoxycarbonylaminophenyl ether

136. 3-Hydroxyphenyl-4'-methoxycarbonylaminophenyl ether

137. 3-Hydroxyphenyl-4'-ethoxycarbonylaminophenyl ether

138. 3-Hydroxyphenyl-4'-n-octyloxycarbonylaminophenyl ether

139. 3-Hydroxyphenyl-4'-(3-chlorobenzyl)oxycarbonylaminophenyl ether

140. 3-Hydroxyphenyl-4'-phenyloxycarbonylaminophenyl ether

141. 3-Hydroxyphenyl-4'-(4-isopropylphenyl)oxycarbonylaminophenyl ether

142. 3-Hydroxyphenyl-4'-(4-allylcarbonylphenyl)oxycarbonylaminophenyl ether

143. 3-Hydroxyphenyl-4'-(4-methylthiophenyl)oxycarbonylaminophenyl ether

144. 3-Hydroxyphenyl-4'-(4-methoxyphenyl)oxycarbonylaminophenyl ether

145. 3-Hydroxyphenyl-4'-(3-chlorophenyl)oxycarbonylaminophenyl ether

146. 3-Hydroxyphenyl-3'-methyl-4'-phenyloxycarbonylaminophenyl ether

147. 4-Hydroxyphenyl-3'-n-butoxycarbonylaminophenyl ether

148. 4-Hydroxyphenyl-3'-cyclohexyloxycarbonylaminophenyl ether

149. 4-Hydroxyphenyl-3'-(3-n-butoxypropyl)oxycarbonylaminophenyl ether

150. 4-Hydroxyphenyl-3'-(3-methylbenzyl)oxycarbonylaminophenyl ether

151. 4 Hydroxyphenyl-3'-phenyloxycarbonylaminophenyl ether

152. 4-Hydroxyphenyl-3'-(4-methylphenyl)oxycarbonylaminophenyl ether

153. 4-Hydroxyphenyl-3'-(4-phenoxyphenyl)oxycarbonylaminophenyl ether

154. 4-Hydroxyphenyl-3'-(3-nitrophenyl)oxycarbonylaminophenyl ether

155. 3-Methyl-4-Hydroxyphenyl-3'-phenyloxycarbonylaminophenyl ether

156. 3-Isopropyl-4-Hydroxyphenyl-3'-phenyloxycarbonylaminophenyl ether

157. 4-Hydroxyphenyl-4'-ethoxycarbonylaminophenyl sulfide

158. 4-Hydroxyphenyl-4'-isobutoxycarbonylaminophenyl sulfide

159. 4-Hydroxyphenyl-4'-n-hexadecyloxycarbonylaminophenyl sulfide

160. 4-Hydroxyphenyl-4'-cyclohexyloxycarbonylaminophenyl sulfide

161. 4-Hydroxyphenyl 4'-(2-methoxyethyl)oxycarbonylaminophenyl sulfide

162. 4-Hydroxyphenyl-4'-(2-benzyloxyethyl)oxycarbonylaminophenyl sulfide

163. 4-Hydroxyphenyl-4'-allyloxycarbonylaminophenyl sulfide

164. 4-Hydroxyphenyl-4'-(2-methylbenzyl)oxycarbonylaminophenyl sulfide

165. 4-Hydroxyphenyl-4'-phenyloxycarbonylaminophenyl sulfide

166. 4-Hydroxyphenyl-4'-(2-naphthyl)oxycarbonylaminophenyl sulfide

167. 4-Hydroxyphenyl-4'-(4-phenylphenyl)oxycarbonylaminophenyl sulfide

168. 4-Hydroxyphenyl-4'-(4-methylphenyl)oxycarbonylaminophenyl sulfide

169. 4-Hydroxyphenyl-4'-(4-chlorophenyl)oxycarbonylaminophenyl sulfide

170. 4-Hydroxyphenyl-4'-(4-methoxycarbonylphenyl)oxycarbonylaminophenyl sulfide

171. 4-Hydroxyphenyl-4'-(4-cumylphenyl)oxycarbonylaminophenyl sulfide

172. 4-Hydroxyphenyl-4'-phenylthiolcarbonylaminophenyl sulfide

173. 3-Hydroxyphenyl-4'-methoxycarbonylaminophenyl sulfide

174. 3-Hydroxyphenyl-4'-(2-chloroethyl)oxycarbonylaminophenyl sulfide

175. 3-Hydroxyphenyl-4'-benzyloxycarbonylaminophenyl sulfide

176. 3-Hydroxyphenyl-4'-phenyloxycarbonylaminophenyl sulfide

177. 3-Hydroxyphenyl-4'-(4-n-butylphenyl)oxycarbonylaminophenyl sulfide

178. 3-Hydroxyphenyl-4'-(4-formylphenyl)oxycarbonylaminophenyl sulfide

179. 3-Hydroxyphenyl-4'-(2,5-dimethylphenyl)oxycarbonylaminophenyl sulfide

180. 3-Hydroxyphenyl-3'-methyl-4'-phenyloxycarbonylaminophenyl sulfide

181. 4-Hydroxyphenyl-3'-n-hexyloxycarbonylaminophenyl sulfide

182. 4-Hydroxyphenyl-3'-cyclohexyloxycarbonylaminophenyl sulfide

183. 4-Hydroxyphenyl-3'-(2-n-hexyloxyethyl)oxycarbonylaminophenyl sulfide

184. 4-Hydroxyphenyl-3'-(4-allylbenzyl)oxycarbonylaminophenyl sulfide

185. 4-Hydroxyphenyl-3'-phenyloxycarbonylaminophenyl sulfide

186. 4-Hydroxyphenyl-3'-(4-allyloxyphenyl)oxycarbonylaminophenyl sulfide

187. 4-Hydroxyphenyl-3'-(4-hydroxyphenyl)oxycarbonylaminophenyl sulfide

188. 4-Hydroxyphenyl-3'-(3,4-dimethylphenyl)oxycarbonylaminophenyl sulfide

189. 3-Methyl-4-Hydroxyphenyl-3'-phenyloxycarbonylaminophenyl sulfide

190. 3-Isopropyl-4-Hydroxyphenyl-3'-phenyloxycarbonylaminophenyl sulfide

191. 4"-Methoxycarbonylaminophenyl-4-(4'-hydroxy)phenylbenzoate

192. 4"-Phenyloxycarbonylaminophenyl-4-(4'-hydroxy)phenylbenzoate

193. 3"-Phenyloxycarbonylaminophenyl-4-(4'-hydroxy)phenylbenzoate

194. 4'-Hydroxyphenyl-4-ethoxycarbonylaminobenzoate

195. 4'-Hydroxyphenyl-4-phenyloxycarbonylaminobenzoate

196. 4-Hydroxy-4'-n-octyloxycarbonylaminobiphenyl

197. 4-Hydroxy-4'-(2,6-dimethylcyclohexyl)oxycarbonylaminobiphenyl

198. 4-Hydroxy-4'-(2-ethoxyethoxyethyl)oxycarbonylaminobiphenyl

199. 4-Hydroxy-4'-(2-benzyloxyethyl)oxycarbonylaminobiphenyl

200. 4-Hydroxy-4'-benzyloxycarbonylaminobiphenyl

201. 4-Hydroxy-4'-phenyloxycarbonylaminobiphenyl

202. 4-Hydroxy-4'-(2-naphthyl)oxycarbonylaminobiphenyl

203. 4-Hydroxy-4'-(4-phenylphenyl)oxycarbonylaminobiphenyl

204. 4-Hydroxy-4'-(4-tert-octylphenyl)oxycarbonylaminobiphenyl

205. 4-Hydroxy-4'-(4-isopropoxyphenyl)oxycarbonylaminobiphenyl

206. 4-Hydroxy-4'-(4-chlorophenyl)oxycarbonylaminobiphenyl

207. 4-Hydroxy-4'-(4-cyanophenyl)oxycarbonylaminobiphenyl

208. 4-Hydroxy-2'-phenyl-4'-methoxycarbonylaminobiphenyl

209. 4-Hydroxy-3,5-diphenyl-4'-phenyloxycarbonylaminobiphenyl

210. 3-Hydroxy-4'-methoxycarbonylaminobiphenyl

211. 3-Hydroxy-4'-(2-chlorobenzyl)oxyoarbonylaminobipheny

212. 3-Hydroxy-4'-phenyloxycarbonylaminobiphenyl

213. 3-Hydroxy-4'-(4-n-propylphenyl)oxycarbonylaminobiphenyl

214. 3-Hydroxy-4'-(2-chlorophenyl)oxycarbonylaminobiphenyl

215. 3-Hydroxy-3'-methyl-4'-phenyloxycarbonylaminobiphenyl

216. 3-Hydroxy-5'-phenyl-4'-methoxycarbonylaminobiphenyl

217. 4-Hydroxy-3'-n-nonyloxycarbonylaminobiphenyl

218. 4-Hydroxy-3'-cyclohexyloxycarbonylaminobiphenyl

219. 4-Hydroxy-3'-phenyloxycarbonylaminobiphenyl

220. 4-Hydroxy-3'-(4-fluorophenyl)oxycarbonylaminobiphenyl

221. 2-Hydroxy-2'-methoxycarbonylaminobiphenyl

222. 1-Hydroxy-4-methoxycarbonylaminonaphthalene

223. 1-Hydroxy-4-(2-ethylhexyl)oxycarbonylaminonaphthalene

224. 1-Hydroxy-4-benzyloxycarbonylaminonaphthalene

225. 1-Hydroxy-4-(4'-methylphenyl)oxycarbonylaminonaphthalene

226. 1-Hydroxy-4-(4'-phenylphenyl)oxycarbonylaminonaphthalene

227. 1-Hydroxy-5-methoxycarbonylaminonaphthalene

228. 1-Hydroxy-5-cyclohexyloxycarbonylaminonaphthalene

229. 1-Hydroxy-5-(4'-acetyloxyphenyl)oxycarbonylaminonaphthalene

230. 2-Hydroxy-7-methoxycarbonylaminonaphthalene

231. 2-Hydroxy-7-phenyloxycarbonylaminonaphthalene

232. 2-Hydroxy-7-(4'-methoxycarbonylphenyl)oxycarbonylaminonaphthalene

233. 2-Hydroxy-6-(4'-isopropoxyphenyl)oxycarbonylaminonaphthalene

234. 2-Hydroxy-8-phenyloxycarbonylaminonaphthalene

235. 2-Hydroxy-8-(4'-cumylphenyl)oxycarbonylaminonaphthalene

236. 1-(4'-hydroxyphenyl)-4-(4"-methoxycarbonylaminophenyl)benzene

237. 1-(4'-hydroxyphenyl)-4-(4"-phenyloxycarbonylaminophenyl)benzene

238. 4-Hydroxy-4'-n-butoxycarbonylaminobenzophenone

239. 4-Hydroxy-4'-(2-naphthyl)oxycarbonylaminobenzophenone

240. 3-Hydroxy-2'-cyclohexyloxycarbonylaminobenzophenone

241. 2-Hydroxy-3'-(4-methylphenyl)oxycarbonylaminobenzophenone

242. 2-Hydroxy-5-methyl-3'-(4-tert-butylphenyl)oxycarbonylaminobenzophenone

243. 3-Hydroxy-2'-(4-cyclohexylphenyl)oxycarbonylamino-5'-chlorobenzophenone

244. 4-Hydroxy-3,5-di-tert-butyl-4'-(4-cumylphenyl)oxycarbonylaminobenzophenone

245. 1-(4'-Hydroxyphenyl)-2-(4"-allyloxycarbonylaminophenyl)ethane

246. 1-(4'-Hydroxyphenyl)-2-[4"-(4-phenylphenyl)oxycarbonylphenyl]ethane

247. 1-(2',5'-Dihydroxyphenyl)-2-[3"-methoxy-4"-(4-methoxyphenyl)oxycarbonylaminophenyl]ethane

248. 1-(3'-Hydroxyphenyl)-3-[3"-(2-methoxyethyl)oxyoarbonylaminophenyl]propane

249. 1-(3'-Hydroxyphenyl)-3-[4"-(3-methoxymethylphenyl)oxycarbonylaminophenyl]propane

250. 1-(4'-Hydroxyphenyl)-2-[4"-(2-n-butoxyethyl)oxycarbonylaminophenyl]ethene

251. 1-(4'-Hydroxyphenyl)-2-[4"-(4-allyloxyphenyl)oxycarbonylaminophenyl]ethene

252. 3-(4'-Hydroxyphenyl)-4-[4"-(2-methoxyethoxyethyl)oxycarbonylaminophenyl]-3-hexene

253. 3-(4'-Hydroxyphenyl)-4-[4"-(4-benzyloxyphenyl)oxycarbonylaminophenyl]-3-hexene

254. 3-(4'-Hydroxyphenyl)-4-[3"-(2-benzyloxyphenyl)oxycarbonylamino-4"-hydroxyphenyl]-3-hexene

255. 1-(4'-Hydroxyphenyl)-4-[4"-(2-allyloxyethyl)oxycarbonylaminophenyl]oxybenzene

256. 1-(4'-Hydroxyphenyl)-4-[4"-(4-octyloxyphenyl)oxycarbonylaminophenyl]oxybenzene

257. 4'-(2-Benzyloxyethyl)oxycarbonylaminophenyl 2-hydroxybenzoate

258. 4'-(4-Phenoxyphenyl)oxycarbonylaminophenyl 2-hydroxybenzoate

259. 3'-(2-Benzyloxyethoxyethyl)oxycarbonylamino-4'-chlorophenyl 4-hydroxy-3,5-di-tert-butylbenzoate

260. 3'-(4-Acetylphenyl)oxycarbonylamino-4'-chlorophenyl 4-hydroxy-3,5-di-tert-butylbenzoate

261. 1-(4'-Hydroxyphenyl)-2-[2"-hydroxy-4"-(2-phenoxyethyl)oxycarbonylaminophenylcarbonyl]ethane

262. 1-(4'-Hydroxyphenyl)-2-[2"-hydroxy-4"-(4-benzylcarbonylphenyl)oxycarbonylaminophenylcarbonyl]ethane

263. 1-(4'-Hydroxyphenyl)-2-[2"-hydroxy-4"-(2-tetrahydrofurfuryl)oxycarbonylaminophenylcarbonyl]ethene

264. 1-(4'-Hydroxyphenyl)-2-[2"-hydroxy-4"-(4-methoxycarbonylphenyl)oxycarbonylaminophenylcarbonyl]ethene

265. 1-(4'-Hydroxyphenyl)-2-[4"-(2-chloroethyl)oxycarbonylaminophenyl]ethene

266. 1-(4'-Hydroxyphenyl)-2-[4"-(4-acetyloxycarbonylphenyl)oxycarbonylaminophenyl]ethene

267. 1-(2',4',6'-Trihydroxyphenylcarbonyl)-1-(4"-benzyloxycarbonylaminophenyl)methane

268. 1-(2',4',6'-Trihydroxyphenylcarbonyl)-1-[4"-(4-phenylcarbonyloxyphenyl)oxycarbonylaminophenyl]methane

269. 3-(4'-Hydroxyphenyl)-4-[4"-(4-chlorobenzyl)oxycarbonylaminophenyl]hexane

270. 3-(4'-Hydroxyphenyl)-4-[4"-(4-methylthiophenyl)oxycarbonylaminophenyl]hexane

271. 1-(4'-Hydroxyphenyloxy)-2-[4"-(4-allylbenzyl)oxycarbonylaminophenyloxy]ethane

272. 1-(4'-Hydroxyphenyloxy)-4-[4"-(4-chlorophenyl)oxycarbonylaminophenyloxy]butane

273. 1-(4'-Hydroxyphenyloxy)-5-[4"-(3-hydroxybenzyl)oxycarbonylaminophenyloxy]pentane

274. 1-(4'-Hydroxyphenyloxy)-6-[4"-(4-nitrophenyl)oxycarbonylaminophenyloxy]hexane

275. 1-(4'-Hydroxyphenylcarbonyl)-1-[4"-(4-hydroxy-3 -methoxybenzyl)oxycarbonylaminophenylcarbonyl]methane

276. 1-(4'-Hydroxyphenylcarbonyl)-1-[4"-(2,4-dimethyl phenyl)oxycarbonylaminophenylcarbonyl]methane

277. 1-(3'-Methoxy-4'-hydroxyphenylcarbonyl)-1-[4"-(4-chlorobenzyl)oxycarbonylaminophenylcarbonyl]methane

278. 1-(3'-Methoxy-4'-hydroxyphenylcarbonyl)-1-[4"-(2,4,6-trichlorophenyl)oxycarbonylaminophenylcarbonyl]methane

279. 1-(4'-Hydroxyphenylcarbonyl)-1-[3"-(2-furfuryl)oxycarbonylaminophenylcarbonyloxy]methane

280. 1-(4'-Hydroxyphenylcarbonyl)-1-[3"-(2,4,6-trimethoxyphenyl)oxycarbonylaminophenylcarbonyloxy]methane

181. 2-(4'-Hydroxyphenyl)-2-(4"-methylaminocarbonyloxyphenyl]propane

182. 2-(4'-Hydroxyphenyl)-2-(4"-n-octylaminocarbonyloxyphenyl)propane

183. 2-(4'-Hydroxyphenyl)-2-(4"-cyclohexylaminocarbonyloxyphenyl)propane

184. 2-(4'-Hydroxyphenyl)-2-[4"-(2-tetrahydrofurfuryl)aminocarbonyloxyphenyl]propane

185. 2-(4'-Hydroxyphenyl)-2-[4"-(2-methoxyethyl)aminocarbonyloxyphenyl]propane

286. 2-(4'-Hydroxyphenyl)-2-[4"-(2-methoxyethoxyethyl)aminocarbonyloxyphenyl]propane

287. 2-(4'-Hydroxyphenyl)-2-[4"-(3-chloropropyl)aminocarbonyloxyphenyl]propane

288. 2-(4'-Hydroxyphenyl)-2-(4"-allylaminocarbonyloxyphenyl)propane

289. 2-(4'-Hydroxyphenyl)-2-[4"-(4-methylbenzyl)aminocarbonyloxyphenyl]propane

290. 2-(4'-H droxyphenyl)-2-(4"-phenylaminocarbonyloxyphenyl)propane

291. 2-(4'-Hydroxyphenyl)-2-[4"-(1-naphthyl)aminocarbonyloxyphenyl]propane

292. 2-(4'-Hydroxyphenyl)-2-[4"-(4-phenylphenyl)aminocarbonyloxyphenyl]propane

293. 2-(4'-Hydroxyphenyl)-2-[4"-(4-methylphenyl)aminocarbonyloxyphenyl]propane

294. 2-(4'-Hydroxyphenyl)-2-[4"-(4-methoxyphenyl)aminocarbonyloxyphenyl]propane

295. 2-(4'-Hydroxyphenyl)-2-[4"-(4-chlorophenyl)aminocarbonyloxyphenyl]propane

296. 2-(4'-Hydroxyphenyl)-2-[4"-(4-acetylphenyl)aminocarbonyloxyphenyl]propane

297. 2-(4'-Hydroxyphenyl)-2-[4"-(4-ethoxycarbonylphenyl)aminocarbonyloxyphenyl]propane

298. 2-(4'-Hydroxyphenyl)-2-[4"-(4-phenylcarbonylphenyl)aminocarbonyloxyphenyl]propane

299. 2-(4'-Hydroxyphenyl)-2-[4"-(2-chloro-6-methylphenyl)aminocarbonyloxyphenyl]propane

300. 2-(4'-Hydroxyphenyl)-2-[4"-(2,4-dimethylphenyl)aminocarbonyloxyphenyl]propane

301. 2-(3'-Methyl-4'-hydroxyphenyl)-2-(3"-methyl-4"-ethylaminocarbonyloxyphenyl)propane

302. 2-(3'-Methyl-4'-hydroxyphenyl)-2-(3"-methyl-4"-phenylaminocarbonyloxyphenyl)propane

303. 2-(3',5'-Di-tert-butyl-4'-hydroxyphenyl)-2-(3",5"-di-tert-butyl-4"-n-butylaminocarbonyloxyphenyl)propane

304. 2-(3'-chloro-4'-hydroxyphenyl)-2-(3"-chloro-4"-phenylaminocarbonyloxyphenyl)propane

305. 1-(4'-Hydroxyphenyl)-1-(4"-phenylaminocarbonyloxyphenyl)cyclopentane

306. 1-(4'-Hydroxyphenyl)-1-(4"-methylaminocarbonyloxyphenyl)cyclohexane

307. 1-(4'-Hydroxyphenyl)-1-(4"-phenylaminocarbonyloxyphenyl)cyclohexane

308. 1-(4'-Hydroxyphenyl)-1-(4"-n-propylaminocarbonyloxyphenyl)cycloheptane

309. 1-(4'-Hydroxyphenyl)-1-(4"-phenylaminocarbonyloxyphenyl)cyclooctane

310. 1-(4'-Hydroxyphenyl)-1-(4"-methylaminocarbonyloxyphenyl)methane

311. 1-(4'-Hydroxyphenyl)-1-(4"-benzylaminocarbonyloxyphenyl)methane

312. 1-(4'-Hydroxyphenyl)-1-(4"-phenylaminocarbonyloxyphenyl)methane

313. 2-(4'-Hydroxyphenyl)-2-(4"-methylaminocarbonyloxyphenyl)butane

314. 2-(4'-Hydroxyphenyl)-2-(4"-phenylaminocarbonyloxyphenyl)isohexane

315. 1-(4'-Hydroxyphenyl)-1-(4"-phenylaminocarbonyloxyphenyl)-1-phenylethane

316. 1-(3'-Methyl-4'-hydroxyphenyl)-1-(3"-methyl-4"-phenylaminocarbonyloxyphenyl)methane

317. 1-(3'-Methyl-4'-hydroxyphenyl)-1-(3"-methyl-4"-(4-chlorophenyl)aminocarbonyloxyphenyl)methane

318. 2-(4'-Hydroxyphenyl)-2-(4"-phenylaminocarbonyloxyphenyl)hexafluoropropane

319. 2-(4'-Hydroxyphenyl)-2-(4"-dimethylaminocarbonyloxyphenyl)propane

320. 2-(4'-Hydroxyphenyl)-2-(4"-N-phenyl-N-methylaminocarbonyloxyphenyl)propane

321. 2-(4'-Hydroxyphenyl)-2-(4"-phenylaminothiocarbonyloxyphenyl)propane

322. 2-(3'-Hydroxyphenyl)-2-(4"-methylaminocarbonyloxyphenyl)propane

323. 2-(4'-Hydroxyphenyl)-2-(3"-ethylaminocarbonyloxyphenyl)propane

324. 2-(2'-Hydroxyphenyl)-2-(4"-phenylaminocarbonyloxyphenyl)propane

325. 2-(4'-Hydroxyphenyl)-2-(2"-n-butylaminocarbonyloxyphenyl)propane

326. 1-(4'-Hydroxyphenyl)-1-(2"-phenylaminocarbonyloxyphenyl)methane

327. 1-(2'-Hydroxyphenyl)-1-(4"-n-butylaminocarbonyloxyphenyl)methane

328. 1-(2'-Hydroxyphenyl)-1-[2"-(4-methylphenyl)aminocarbonyloxyphenyl)methane

329. 4-Hydroxyphenyl-4'-methylaminocarbonyloxyphenyl ether

330. 4-Hydroxyphenyl-4'-n-hexylaminocarbonyloxyphenyl ether

331. 4-Hydroxyphenyl-4'-n-hexadecylaminocarbonyloxyphenyl ether

332. 4-Hydroxyphenyl-4'-cyclohexylaminocarbonyloxyphenyl ether

333. 4-Hydroxyphenyl-4'-(2-methoxyethyl)aminocarbonyloxyphenyl ether

334. 4-Hydroxyphenyl-4'-benzylaminocarbonyloxyphenyl ether

335. 4-Hydroxyphenyl-4'-phenylaminocarbonyloxyphenyl ether

336. 4-Hydroxyphenyl-4'-(4-methylphenyl)aminocarbonyloxyphenyl ether

337. 4-Hydroxyphenyl-4'-(3-chlorophenyl)aminocarbonyloxyphenyl ether

338. 4-Hydroxyphenyl-4'-(2,4-dimethylphenyl)aminocarbonyloxyphenyl ether

339. 4-Hydroxyphenyl-4'-phenylaminothiocarbonyloxyphenyl ether

340. 2-Hydroxyphenyl-2'-methylaminocarbonyloxyphenyl ether

341. 2-Hydroxyphenyl-2'-(4-methylbenzyl)aminocarbonyloxyphenyl ether

342. 2-Hydroxyphenyl-2'-phenylaminocarbonyloxyphenyl ether

343. 2-Hydroxyphenyl-2'-(4-methoxyphenyl)aminocarbonyloxyphenyl ether

344. 2-Hydroxyphenyl-2'-(4-chlorophenyl)aminocarbonyloxyphenyl ether

345. 2-Hydroxyphenyl-2'-(3-chlorophenyl)aminocarbonyloxyphenyl ether

346. 4-Hydroxyphenyl-4'-ethylaminocarbonyloxyphenyl sulfide

347. 4-Hydroxyphenyl-4'-n-octylaminocarbonyloxyphenyl sulfide

348. 4-Hydroxyphenyl-4'-cyclohexylaminocarbonyloxyphenyl sulfide

349. 4-Hydroxyphenyl-4'-(2-phenoxyethyl)aminocarbonyloxyphenyl sulfide

350. 4-Hydroxyphenyl-4'-allylaminocarbonyloxyphenyl sulfide

351. 4-Hydroxyphenyl-4'-(4-methylbenzyl)aminocarbonyloxyphenyl sulfide

352. 4-Hydroxyphenyl-4'-phenylaminocarbonyloxyphenyl sulfide

353. 4-Hydroxyphenyl-4'-(2-chlorophenyl)aminocarbonyloxyphenyl sulfide

354. 4-Hydroxyphenyl-4'-(4-acetyloxyphenyl)aminocarbonyloxyphenyl sulfide

355. 4-Hydroxyphenyl-4'-(4-chloro-3-methylphenyl)aminocarbonyloxyphenyl sulfide

356. 4-Hydroxyphenyl-4'-(2,4-dimethylphenyl)aminocarbonyloxyphenyl sulfide

357. 3-Methyl-4-Hydroxyphenyl-3'-methyl-4'-phenylaminocarbonyloxyphenyl sulfide

358. 3,5-Dichloro-4-Hydroxyphenyl-3',5'-dichloro-4'-phenylaminocarbonyloxyphenyl sulfide

359. 4-Hydroxyphenyl-4'-phenylaminothiocarbonyloxyphenyl sulfide

360. 2-Hydroxyphenyl-2'-methylaminocarbonyloxyphenyl sulfide

361. 2-Hydroxyphenyl-2'-phenylaminocarbonyloxyphenyl sulfide

362. 2-Hydroxy-3,5-dichlorophenyl-2'-phenylaminocarbonyloxy-3',5'-dichlorophenyl sulfide

363. 4-Hydroxyphenyl-4'-phenylaminocarbonyloxyphenyl sulfoxide

364. 4-Hydroxyphenyl-4'-phenylaminocarbonyloxyphenyl sulfone

365. 4"-Methylaminocarbonyloxyphenyl-4-(4'-hydroxy)phenylbenzoate

366. 4"-Phenylaminocarbonyloxyphenyl 4-(4'-hydroxy)phenylbenzoate

367. 4-Hydroxyphenyl 4-n-butylaminocarbonyloxybenzoate

368. 4-Hydroxyphenyl 4-phenylaminocarbonyloxybenzoate

369. 4-Hydroxy-4'-ethylaminocarbonyloxybiphenyl

370. 4-Hydroxy-4'-cyclohexylaminocarbonyloxybiphenyl

371. 4-Hydroxy-4'-(2-methoxyethyl)aminocarbonyloxybiphenyl

372. 4-Hydroxy-4'-benzylaminocarbonyloxybiphenyl

373. 4-Hydroxy-4'-phenylaminocarbonyloxybiphenyl

374. 4-Hydroxy-4'-(4-methoxyphenyl)aminocarbonyloxybiphenyl

375. 3,5-Di-tert-butyl-4-hydroxy-3',5'-di-tert-butyl-4'-phenylaminocarbonyloxybiphenyl

376. 2-Hydroxy-2'-n-propylaminocarbonyloxybiphenyl

377. 2-Hydroxy-2'-phenylaminocarbonyloxybiphenyl

378. 1-Hydroxy-4-methylaminocarbonyloxynaphthalene

379. 1-Hydroxy-4-phenylaminocarbonyloxynaphthalene

380. 1-Hydroxy-4-methylaminothiocarbonyloxynaphthalene

381. 1-Hydroxy-5-methylaminocarbonyloxynaphthalene

382. 2-Hydroxy-1-methylaminocarbonyloxynaphthalene

383. 2-Hydroxy-5-ethylaminocarbonyloxynaphthalene

384. 2-Hydroxy-8-methylaminocarbonyloxynaphthalene

385. 2-Hydroxy-8-phenylaminocarbonyloxynaphthalene

386. 1,8-Dihydroxy-4-n-butylaminocarbonyloxynaphthalene

387. 1,8-Dihydroxy-4-methylaminothiocarbonyloxynaphthalene

Examples of the colorless or slightly-colored electron-donating chromogenic compounds usable in the present invention include triarylmethane compounds, diarylmethane compounds, Rhodamine-lactam compounds, fluoran compounds, indolylphthalide compounds, pyridine compounds, spiro compounds and fluorene compounds.

Specific examples of the triarylmethane compounds include 3,3-bis(4-dimethylaminophenyl)-6-dimethylaminophthalide [also called "crystal violet lactone"], 3,3-bis(4-dimethylaminophenyl)phthalide, 3-(4-dimethylaminophenyl)-3-(1,3-dimethylindol-3-yl)phthalide, 3-(4-dimethylaminophenyl)- 3-(2-methylindol-3-yl)phthalide, 3,3-bis(9-ethylcarbazol-3-yl)-6-dimethylaminophthalide, 3-(4-dimethylaminophenyl)-3-(1-methylpyrrol-3-yl)-6-dimethylaminophthalide and 3,3-bis[2,2-bis(4-dimethylaminophenyl)ethenyl]-4,5,6,7-tetrachlorophthalide.

Specific examples of the diarylmethane compounds include 4,4-bis-dimethylaminobenzhydrinbenzyl ether, N-halophenyl-leucoauramines and N-2,4,5-trichlorophenylleucoauramine.

Specific examples of the Rhodamine-lactam compounds include Rhodamine-B-anilinolactam, Rhodamine-(4-nitroanilino)lactam and Rhodamine-B-(4-chloroanilino)lactam.

Specific examples of the fluoran compounds include 3,6-dimethoxyfluoran, 3-dimethylamino-7-methoxyfluoran, 3-diethylamino-6-methoxyfluoran, 3-diethylamino-7-methoxyfluoran, 3-diethylamino-7-chlorofluoran, 3-diethylamino-6-methyl-7-chlorofluoran, 3-diethylamino-6,7-dimethylfluoran, 3-N-cyclohexyl-N-n-butylamino-7-methylfluoran, 3-diethylamino-7-dibenzylaminofluoran, 3-diethylamino-7-n-octylaminofluoran, 3-diethylamino-7-di-n-hexylaminofluoran, 3-diethylamino-7-anilinofluoran, 3-diethylamino-7-(2-chloroanilino)fluoron, 3-diethylamino-7-(3-chloroanilino)fluoran, 3-diethylamino-7-(2,3-dichloroanilino)fluoran, 3-diethylamino- 7-(3-trifluoromethylanilino)fluoran, 3-di-n-butylamino-7-(2-chloroanilino)fluoran, 3-diethylamino-6-chloro-7-anilinofluoran, 3-di-n-butylamino-6-chloro 7-anilinofluoran, 3-diethylamino-6-methoxy-7-anilinofluoran, 3-di-n-butylamino-6-ethoxy-7-anilinofluoran, 3-pyrrolidino-6-methyl-7-anilinofluoran, 3-morpholino-6-methyl-7-anilinofluoran, 3-dimethylamino-6-methyl-7-anilinofluoran, 3-diethylamino-6-methyl-7-anilinofluoran, 3-di-n-butylamino-6-methyl-7-anilinofluoran, 3-di-n-pentylamino-6-methyl-7-anilinofluoran, 3-di-n-octylamino-6-methyl-7-anilinofluoran, 3-N-ethyl-N-methylamino-6-methyl-7-anilinofluoran, 3-N-n-propyl-N-methylamino-6-methyl-7-anilinofluoran, 3-N-n-propyl-N-ethylamino-6-methyl-7-anilinofluoran, 3-N-isopropyl-N-methylamino-6-methyl-7-anilinofluoran, 3-N-n-butyl-N-methylamino-6-methyl-7-anilinofluoran, 3-N-n-butyl-N-n-ethylamino-6-methyl-7-anilinofluoran, 3-N-n-butyl-N-n-propylamino-6-methyl-7-anilinofluoran, 3-N-isobutyl-N-methylamino-6-methyl-7-anilinofluoran, 3-N-isobutyl-N-ethylamino-6-methyl-7-anilinofluoran, 3-N-isopentyl-N-ethylamino-6-methyl-7-anilinofluoran, 3-N-n-hexyl-N-ethylamino-6-methyl-7-anilinofluoran, 3-N-n-octyl-N-ethylamino-6-methyl-7-anilinofluoran, 3-N-cyclohexyl-N-methylamino-6-methyl-7-anilinofluoran, 3-N-cyclohexyl-N-n-propylamino-6-methyl-7-anilinofluoran, 3-N-cyclohexyl-N-n-butylamino- 6-methyl-7-anilinofluoran, 3-N-cyclohexyl-N-n-pentylamino-6-methyl-7-anilinofluoran, 3-N-cyclohexyl-N-n-hexylamino-6-methyl 7-anilinofluoran, 3-N-cyclohexyl-N-n-heptylamino-6-methyl-7-anilinofluoran, 3-N-cyclohexyl-N-n-octylamino-6-methyl-7-anilinofluoran, 3-N-cyclohexyl-N-n-decylamino-6-methyl-7-anilinofluoran, 3-N-2'-methoxyethyl-N-methylamino-6-methyl-7-anilinofluoran, 3-N-2'-methoxyethyl-N-ethylamino-6-methyl-7-anilinofluoran, 3-N-2'-ethoxyethyl-N-methylamino-6-methyl-7-anilinofluoran, 3-N-2'-ethoxyethyl-N-ethylamino-6-methyl-7-anilinofluoran, 3-N-3'-methoxypropyl-N-methylamino-6-methyl-7-anilinofluoran, 3-N-3'-ethoxypropyl-N-methylamino-6-methyl-7-anilinofluoran, 3-N-2'-methoxyethyl-N-isobutylamino-6-methyl-7-anilinofluoran, 3-N-2'-tetrahydrofurfuryl-N-ethylamino-6-methyl-7-anilinofluoran, 3-N-(4'-methylphenyl)-N-ethylamino-6-methyl-7-anilinofluoran, 3-diethylamino-6-ethyl-7-anilinofluoran, 3-di-ethylaminoamino)fluoran, 3-di-n-6-methyl-7-(2',6'-dimethylphenyl butylamino-6-methyl-7-(2',6'-dimethylphenylamino)fluoran, 3-di-n-butylamino-7-(2',6'-dimethylphenylamino)fluoran and 2,2-bis[4'(3-N-cyclohexyl-N-methylamino-6-methylfluoran)-7-ylaminophenyl]propane.

Specific examples of the indolylphthalide compounds include 3,3-bis(1-ethyl-2-methylindol-3-yl)phthalide, 3,3-bis(1-octyl-2-methylindol-3-yl)phthalide, 3-(2-ethoxy-4-diethylaminophenyl)-3-(1-ethyl-2-methylindol-3-yl)phthalide, 3-(2-ethoxy-4-dibutylaminophenyl)-3-(1-ethyl-2-methylindol-3-yl)phthalide and 3-(2-ethoxy-4-diethylaminophenyl)-3-(1-octyl-2-methylindol-3-yl)phthalide.

Specific examples of the pyridine compounds include 3-(2-ethoxy-4-diethylaminophenyl)-3-(1-octyl-2-methylindol-3-yl)-4- and -7-azaphthalides, 3-(2-ethoxy-4-diethylaminophenyl)-3-(1-ethyl-2-methylindol-3-yl)-4- and -7-azaphthalides, 3-(2-hexyloxy-4-diethylaminophenyl)-3-(1-ethyl-2-methylindol-3-yl)-4- and -7-azapthalides, 3-(2-ethoxy-4-diethylaminophenyl)-3-(1-ethyl-2-phenylindol-3-yl)-4- and -7-azaphthalides, and 3-(2-butoxy-4-diethylaminophenyl)-3-(1-ethyl-2-phenylindol-3-yl)-4- and -7-azaphthalides.

Specific examples of the spiro compounds include 3-methyl-spiro-dinaphthopyran, 3-ethyl-spiro-dinaphthopyran, 3-phenyl-spiro-dinaphthopyran, 3 benzyl-spirodinaphthopyran, 3-methyl-naphtho-(3-methoxybenzo)spiropyran and 3-propyl-spiro-dibenzopyran.

Specific examples of the fluorene compounds include 3',6'-bisdiethylamino-5-diethylaminospiro(isobenzofuran-1,9'-fluoren)-3-on and 3',6'-bisdiethylamino-7-diethylamino-2-methylspiro(1,3-benzooxazine-4,9'-fluorene).

These electron-donating chromogenic compounds can be used either singly or, to adjust the tone of color images to be produced or to obtain a multi-color heat-sensitive recording material or for other purposes, in combination.

In the heat-sensitive recording material according to the present invention, it is generally desirable to use the electron-attracting compound in an amount of 50-700 parts by weight, preferably 100-500 parts by weight per 100 parts by weight of the electron-donating chromogenic compound. As has already been mentioned above, the heat-sensitive recording material according to this invention can also use, as an electron-attracting compound, an electron-attracting compound other than the compound represented by the formula (1) or (2) in combination with the latter compound.

In particular, a heat-sensitive recording material using, as an electron-attracting compound, the compound represented by the formula (1) or (2) in combination with another electron-attracting compound is excellent in the storage stability (hydrothermo-resistance, waterproofness, oil resistance, etc.) of color images to be produced, and is preferred.

In this case, it is generally desirable to control the proportion of the compound represented by the formula (1) or (2) to at least 5 wt. %, preferably 20 wt. % or more, more preferably 30 wt. % or more, all based on the whole electron-attracting compounds.

Examples of electron-attracting compounds other than the compounds represented by the formula (1) or (2) include organic electron-attracting compounds such as phenol derivatives, organic acids and metal salts thereof, complexes and urea derivatives; and inorganic electron-attracting compounds such as acid clay.

Specific examples of these compounds include organic electron-attracting compounds, for example, phenol derivatives such as 4-tert-butylphenol, 4-tertoctylphenol, 4-phenylphenol, 1-naphthol, 2-naphthol, hydroquinone, resorcinol, 4-tert-octylcatechol, 2,2'-dihydroxydiphenyl, 2,2-bis(4'-hydroxyphenyl)propane [also called "bisphenol A"], 1,1-bis(4'-hydroxyphenyl)cyclohexane, 2,2-bis(4'-hydroxy-3'-methylphenyl)propane, ethyl 2,2-bis(4'-hydroxyphenyl)acetate, n-butyl 4,4-(4'-hydroxyphenyl)pentanoate, benzyl 4-hydroxybenzoate, phenethyl 4-hydroxybenzoate, phenoxyethyl 2,4-dihydroxybenzoate, dimethyl 4-hydroxyphthalate, hydroquinonmonobenzyl ether, bis(3-methyl-4-hydroxyphenyl) sulfide, bis(2-methyl-4-hydroxyphenyl) sulfide, bis(3-phenyl-4-hydroxyphenyl) sulfide, bis(3-cyclohexyl-4-hydroxyphenyl) sulfide, bis(4-hydroxyphenyl) sulfoxide, bis(4-hydroxyphenyl) sulfone, bis(3-allyl-4-hydroxyphenyl) sulfone, 4-hydroxy-4'-methyldiphenyl sulfone, 4-hydroxy-4'-chlorodiphenyl sulfone, 4-hydroxy-4'-n-propoxydiphenyl sulfone, 4-hydroxy-4'-isopropoxydiphenyl sulfone, 4-hydroxy-4'-n-butoxydiphenyl sulfone, 3,4-dihydroxy-4'-methyldiphenyl sulfone, bis(2-hydroxy-4-tert-butylphenyl) sulfone, bis(2-hydroxy-4-chlorophenyl) sulfone, 4-hydroxybenzophenone, 2,4-dihydroxybenzophenone, 1,7-di(4-hydroxyphenylthio)3,5-dioxaheptane and 1,5-di(4-hydroxyphenylthio)-3-oxapentane, organic acids such as salicyclic acid, 3-isopropylsalicyclic acid, 3-cyclohexylsalicyclic acid, 3,5-di-tert-butylsalicyclic acid, 3,5-di-α-methylbenzylsalicyclic acid, 3-methyl-5-α-methylbenzylsalicyclic acid, 4-[2'-(4-methoxyphenyloxy)ethyloxy]salicylic acid, 2-hydroxy-3-naphthoic acid, 2-hydroxy-6-naphthoic acid, monobenzyl phthalate and monophenyl phthalate and metallic salts thereof (ex. nickel, zinc, aluminum and calcium salts), complexes such as zinc thiocyanate/antipyrine complexes and molybdic acid/acetylacetone complexes and urea derivatives such as phenylthiourea, di(3-trifluoromethylphenyl)thiourea and 1,4-di(3'-chlorophenyl)-3-thiosemicarbazide; and inorganic electron-attracting compounds such as acid clay, attapulgite, activated clay, aluminum chloride, zinc chloride and zinc bromide. Among them, phenol derivatives are particularly preferred as electron-attracting compounds.

These electron-attracting compounds can be used either singly or in combination.

In addition, in the heat-sensitive recording material according to the present invention, a thermofusible compound (a compound whose melting point is 60°-150° C., preferably about 80°-100° C.) can be added further to improve the color-producing sensitivity, if desired. This is preferred as it makes it possible to obtain a heat-sensitive recording material which is good in color-producing sensitivity and excellent in the storage stability of a color image to be produced. Particularly preferred are heat-sensitive recording materials using, as an electron-attracting compound, the compound represented by the formula (1) or (2) and the above-mentioned, known, electron-attracting compound (for example, one of the various phenol derivatives) in combination and heat-sensitive recording materials added further with a thermofusible compound.

In this case, it is generally desirable to use the thermofusible compound in an amount of 10-700 parts by weight, preferably 20-500 parts by weight per 100 parts by weight of the electron-donating chromogenic compound. Specific examples of such thermofusible compounds include nitrogen-containing compounds such as stearic acid amide, palmitic acid amide stearyl urea, N-ethylcarbazole and 4-methoxydiphenylamine; esters such as benzyl 4-benzyloxybenxoate phenyl 2-naphthoate, phenyl 1-hydroxy-2-naphthoate, dibenzyl oxalate, di(4-methylbenzyl) oxalate, di(4-chlorobenzyl) oxalate, diphenacyl glutarate, di(4-methylphenyl) carbonate and dibenzyl terephthalate; hydrocarbon compounds such as 4-benzylbiphenyl, m-terphenyl, fluorene and fluoranthene; and ether compounds such as 2-benzyloxynaphthalene, 2-(4'-methylbenzyloxy)naphthalene, 1,4-diethoxynaphthalene, 1,2-bis(3'-methylphenoxy)ethane, 1-phenoxy-2-(4-ethylphenoxy)ethane, 4-(4'-methylphenoxy)biphenyl, 1,4-bis(2'-chlorobenzyloxy)benzene, 4,4'-di-n-butoxydiphenyl sulfone, 1,2-diphenoxybenzene, 1,4-bis(3'-methylphenyloxymethyl)benzene and 4-chlorobenzyloxy(4'-ethoxybenzene). The ester compounds, hydrocarbon compounds and ether compounds are particularly preferred as thermofusible compounds.

These thermofusible compounds can be used either singly or in combination.

To produce the heat-sensitive recording material according to this invention, a conventional process can be followed without the need for relying upon any special process. In the heat-sensitive recording materials according to this invention, no particular limitation is imposed on the method for the formation of the recording layer. For example, a coating formulation for the heat-sensitive recording layer can be coated on a base by a suitable coating means such as an air knife coater, blade coater, bar coater, gravure coater, curtain coater or wire bar, and then dried to form a recording layer.

The coating formulation for the heat-sensitive recording layer can be prepared, generally, by separately grinding and dispersing an electron-donating chromogenic compound, the compound represented by the formula (1) or (2), etc., normally to 3 μm or smaller, preferably to 1.5 μm or smaller in a water-soluble binder in an apparatus such as a ball mill or sand mill and then mixing the resultant dispersions.

Specific examples of usable water-soluble binders include polyvinyl alcohol, hydroxyethylcellulose, hydroxypropylcellulose, epichlorohydrin-modified polyamide, ethylene-maleic anhydride copolymer, styrene-maleic anhydride copolymer, isobutylene-maleic anhydride copolymer, polyacrylic acid, polyacrylamide, methylol-modified polyacrylamide, starch derivatives, casein, gelatin, methylcellulose, carboxymethylcellulose, gum arabic, and carboxyl-modified polyvinyl alcohol.

The recording layer of the heat-sensitive recording material according to this invention can be added, as needed, with a pigment, a water-insoluble binder, a metal soap, a wax, a surfactant, an ultraviolet absorber, a hindered phenol, a defoaming agent, etc.

Usable examples of pigments include zinc oxide, zinc carbonate, calcium carbonate, magnesium carbonate, barium carbonate, barium sulfate, titanium oxide, talc, agalmatolite, kaolin, diatomaceous earth, aluminum hydroxide, magnesium hydroxide, alumina, silica, amorphous silica, urea-formaldehyde filler, polyethylene particles, and cellulose filler.

As the water-insoluble binder, a synthetic rubber latex or synthetic resin emulsion is usually employed. Known examples include styrene-butadiene rubber latex, acrylonitrile-butadiene latex, methyl acrylatebutadiene rubber latex, and vinyl acetate emulsion. They can be used as needed.

As the metal soap, a higher fatty acid metal salt is used. Usable examples include zinc stearate, calcium stearate, and aluminum stearate.

Illustrative examples of waxes include paraffin wax, microcrystalline wax, carboxyl-modified paraffin wax, carnauba wax, polyethylene wax, polystyrene wax, and higher fatty acid esters.

Examples of surfactants include alkali metal sulfosuccinates and fluorine-containing surfactants.

Examples of ultraviolet absorbers include cinnamic acid derivatives, benzophenone derivatives, benzotriazolylphenol derivatives.

Preferred as the hindered phenol is a phenol derivative with a branched alkyl group substituted to at least one of the ortho positions relative to the phenolic hydroxyl group. Examples include 1,1,3-tris-(2-methyl-4-hydroxy-5-tert-butylphenyl)butane, 1,1,3-tris(2-methyl-4-hydroxy-5-cyclohexylphenyl)butane, 1,1,3-tris(2-ethyl-4-hydroxy-5-tert-butylphenyl)butane, 1,1,3-tris(3,5-di-tert-butyl-4-hydroxyphenyl)butane, 1,1,3-tris(2-methyl-4-hydroxy-5-tert-butylphenyl)propane, 2,2-methylene-bis-(6-tert-butyl-4-methylphenol), 2,2-methylene-bis-(6-tert-butyl-4-ethylphenol), 1,3,5-trimethyl-2,4,6-tris(3,5-di-tert-butyl-4-hydroxybenzyl)benzene, 1,3,5-tris(4-tert-butyl-3-hydroxy-2,6-dimethylbenzyl)isocyanuric acid, 1,3,5-tris-(4-tert-butyl-3-hydroxy-2-methyl-6-ethylbenzyl)isocyanuric acid, and bis(2-methyl-4-hydroxy-5-tertbutylphenyl) sulfide.

No particular limitation is imposed on the amount of the coating formulation to be applied. It can be coated in an amount sufficient to give a dry weight in a range of 1.5-12 g/m², preferably 2.5-10 g/m². As the base, a paper sheet, plastic sheet, a synthetic paper sheet or the like can be used.

Various techniques known in the production of heat-sensitive recording materials can be applied a needed. For example, a protective layer can be arranged on the upper and/or lower surfaces of the heat-sensitive recording layer, or a prime coat can be provided between the base and the heat-sensitive recording layer. Further, tackifying treatment can also be applied.

The present invention will hereinafter be described specifically by the following preparation examples and examples. It should however be borne in mind that this invention is by no means limited to or by the examples. In the examples, all designations of "%" mean wt. %.

PREPARATION EXAMPLE 1 Preparation of Exemplified Compound No. 1

Methyl chloroformate (22.7 g) was added dropwise to a suspension of 45.4 g of 2-(4'-hydroxyphenyl)-2-(4"-aminophenyl)propane and 10.6 g of sodium carbonate in 300 ml of ethyl acetate. After they were reacted at room temperature under stirring for 12 hours, the reaction mixture was filtered. Water (200 ml) was added to the resultant filtrate to wash the same. That procedure was repeated until the water layer became neutral. The reaction mixture was allowed to separate into layers. The ethyl acetate layer was collected and, then, ethyl acetate was distilled off under reduced pressure at 40° C., whereby a slightly yellowish crude product was obtained in a solid form. The product was recrystallized from 150 ml of toluene and then dried at 40° C. for 24 hours, whereby 51.3 g of 2-(4'-hydroxyphenyl)-2-(4"-methoxycarbonylaminophenyl)propane were obtained as white crystals.

Yield: 90%.

Melting Point: 104°-105.5° C.

¹ H-NMR, δ(CDCl₃): 1.6(s,6H), 3.8(s,3H), 5.1(s,1H), 6.5-7.4(m,9H).

PREPARATION EXAMPLE 2 Preparation of Exemplified Compound No. 2

In a similar manner to Preparation Example 1 except for the replacement of methyl chloroformate by n-propyl chloroformate, 2-(4'-hydroxyphenyl)-2-(4"-n-propoxycarbonylaminophenyl)propane was obtained.

Melting Point: 146°-147.5° C.

¹ H-NMR, δ(CDCl₃): 0.8-1.1(t,3H), 1.6(s,6H), 1.7-1.9(m,2H), 4.0-4.2(t,2H), 5.4(s,1H), 6.5-7.4(m,9H).

PREPARATION EXAMPLE 3 Preparation of Exemplified Compound No. 3

In a similar manner to Preparation Example 1 except for the replacement of methyl chloroformate by n-butyl chloroformate, 2-(4'-hydroxyphenyl)-2-(4"-n-butoxycarbonylaminophenyl)propane was obtained.

Melting Point: 89°-91° C.

¹ H-NMR, δ(CDCl₃): 0.9-1.1(t,3H), 1.3-1.9(m,10H), 4.1-4.3(m,2H), 5.4-5.6(br,1H), 6.6-7.4(m,9H).

PREPARATION EXAMPLE 4 Preparation of Exemplified Compound No. 5

In a similar manner to Preparation Example 1 except for the replacement of methyl chloroformate by n-hexadecyl chloroformate, 2-(4'-hydroxyphenyl)-2-(4"-n-hexadecyloxycarbonylaminophenyl)propane was obtained.

Melting Point: 63.5°-65° C.

¹ H-NMR, δ(CDCl₃): 0.9-1.1(t,3H), 1.1-2.0(m,36H), 4.1-4.3(t,2H), 5.4-5.6(br,1H), 6.6-7.4(m,9H).

PREPARATION EXAMPLE 5 Preparation of Exemplified Compound No. 6

In a similar manner to Preparation Example 1 except for the replacement of methyl chloroformate by cyclohexyl chloroformate, 2-(4'-hydroxyphenyl)-2-(4"-cyclohexyloxycarbonylaminophenyl)propane was obtained.

Melting Point: 136°-137.5° C..

¹ H-NMR, δ(CDCl₃): 1.1-2.1(m,16H), 4.7-4.9(br,1H), 5.3-5.5(br,1H), 6.5-7.5(m,9H).

PREPARATION EXAMPLE 6 Preparation of Exemplified Compound No. 9

In a similar manner to Preparation Example 1 except for the replacement of methyl chloroformate by 2-methoxyethyl chloroformate, 2-(4'-hydroxyphenyl)-2-[4"-(2-methoxyethyl)oxycarbonylaminophenyl]propane was obtained.

Melting Point: 84°-86° C.

¹ H-NMR, δ(CDCl₃): 1.6(s,6H), 3.4(s,3H),

3.6-3.8(m,2H), 4.2-4.4(m,2H), 5.8-6.0(br,1H), 6.6-7.4(m,9H).

PREPARATION EXAMPLE 7 Preparation of Exemplified Compound No. 14

In a similar manner to Preparation Example 1 except for the replacement of methyl chloroformate by 2-phenoxyethyl chloroformate, 2-(4'-hydroxyphenyl)-2-[4"-(2-phenoxyethyl)oxycarbonylaminophenyl]propane was obtained.

Melting Point: 98°-100° C.

¹ H-NMR, δ(CDCl₃): 1.6(s,6H), 4.1-4.3(m,2H), 4.4-4.6(m,2H), 5.3-5.5(br,1H), 6.6-7.4(m,14H).

PREPARATION EXAMPLE 8 Preparation of Exemplified Compound No. 17

In a similar manner to Preparation Example 1 except for the replacement of methyl chloroformate by allyl chloroformate, 2-(4'-hydroxyphenyl)-2-(4"-allyloxycarbonylaminophenyl)propane was obtained.

Melting Point: 109°-111° C.

¹ H-NMR, δ(CDCl₃): 1.6(s,6H), 4.6-4.8(d,2H), 5.1-5.5(m,3H), 5.7-6.2(m,1H), 6.6-7.4(m,9H).

PREPARATION EXAMPLE 9 Preparation of Exemplified Compound No. 18

In a similar manner to Preparation Example 1 except for the replacement of methyl chloroformate by benzyl chloroformate, 2-(4'-hydroxyphenyl)-2-(4"-benzyloxycarbonylaminophenyl)propane was obtained.

Melting Point: 69°-74° C..

¹ H-NMR, δ(CDCl₃): 1.6(s,6H), 5.0-5.2(m,2H), 5.3(s,1H), 6.6-7.4(m,14H).

PREPARATION EXAMPLE 10 Preparation of Exemplified Compound No. 23

In a similar manner to Preparation Example 1 except for the replacement of methyl chloroformate by 2-phenylethyl chloroformate, 2-(4'-hydroxyphenyl)-2-[4"-(2-phenylethyl)oxycarbonylaminophenyl]propane was obtained.

Melting Point: 121°-123° C.

¹ H-NMR, δ(CDCl₃): 1.6(s,6H), 2.8-3.1(t,2H), 4.2-4.5(t,2H), 5.4-5.5(br,1H), 6.6-7.4(m,14H).

PREPARATION EXAMPLE 11 Preparation of Exemplified Compound No. 24

In a similar manner to Preparation Example 1 except for the replacement of methyl chloroformate by phenyl chloroformate, 2-(4'-hydroxyphenyl)-2-(4"-phenyloxycarbonylaminophenyl)propane was obtained.

Melting Point: 116°-120° C.

¹ H-NMR, δ(CDCl₃): 1.6(s,6H), 5.3(s,1H), 6.6-7.5(m,14H).

PREPARATION EXAMPLE 12 Preparation of Exemplified Compound No. 26

In a similar manner to Preparation Example 1 except for the replacement of methyl chloroformate by 4-phenylphenyl chloroformate, 2-(4'-hydroxyphenyl)-2-[4"-(4-phenylphenyl)oxycarbonylaminophenyl]propane was obtained.

Melting Point: 171°-173° C.

¹ H-NMR, δ(CDCl₃): 1.6(s,6H), 5.3(s,1H), 6.6-7.5(m,18H).

PREPARATION EXAMPLE 13 Preparation of Exemplified Compound No. 27

In a similar manner to Preparation Example 1 except for the replacement of methyl chloroformate by 4-methylphenyl chloroformate, 2-(4'-hydroxyphenyl)-2-[4"-(4-methylphenyl)oxycarbonylaminophenyl]propane was obtained.

Melting Point: 146°-148° C.

¹ H-NMR, δ(CDCl₃): 1.6(s,6H), 2.4(s,3H), 4.5(br,1H), 6.6-7.4(m,13H).

PREPARATION EXAMPLE 14 Preparation of Exemplified Compound No. 28

In a similar manner to Preparation Example 1 except for the replacement of methyl chloroformate by 3-methylphenyl chloroformate, 2-(4'-hydroxyphenyl)-2-[4"-(3-methylphenyl)oxycarbonylaminophenyl]propane was obtained.

Melting Point: 133°-136° C.

¹ H-NMR, δ(CDCl₃): 1.6(s,6H), 2.4(s,3H), 5.0(br,1H), 6.6-7.4(m,13H).

PREPARATION EXAMPLE 15 Preparation of Exemplified Compound No. 30

In a similar manner to Preparation Example 1 except for the replacement of methyl chloroformate by 4-cumylphenyl chloroformate, 2-(4'-hydroxyphenyl)-2-[4"-(4-cumylphenyl)oxycarbonylaminophenyl]propane was obtained.

Melting Point: 146°-148° C.

¹ H-NMR, δ(CDCl₃): 1.5-1.7(m,12H), 4.8(s,1H), 6.6-7.4(m,18H).

PREPARATION EXAMPLE 16 Preparation of Exemplified Compound No. 31

In a similar manner to Preparation Example 1 except for the replacement of methyl chloroformate by 4-methoxyphenyl chloroformate, 2-(4'-hydroxyphenyl)-2-[4"-(4-methoxyphenyl)oxycarbonylaminophenyl]propane was obtained.

Melting Point: 125°-127° C.

¹ H-NMR, δ(CDCl₃): 1.6(s,6H), 3.8(s,3H), 5.0(br,1H), 6.6-7.4(m,13H).

PREPARATION EXAMPLE 17 Preparation of Exemplified Compound No. 33

In a similar manner to Preparation Example 1 except for the replacement of methyl chloroformate by 4-chlorophenyl chloroformate, 2-(4'-hydroxyphenyl)-2-[4"-(4-chlorophenyl)oxycarbonylaminophenyl]propane was obtained.

Melting Point: 162°-164° C.

¹ H-NMR, δ(CDCl₃): 1.6(s,6H), 4.6(s,1H), 6.6-7.4(m,13H).

PREPARATION EXAMPLE 18 Preparation of Exemplified Compound No. 34

In a similar manner to Preparation Example 1 except for the replacement of methyl chloroformate by 2-chlorophenyl chloroformate, 2-(4'-hydroxyphenyl)-2-[4"-(2-chlorophenyl)oxycarbonylaminophenyl]propane was obtained.

Melting Point: 97°-99° C.

¹ H-NMR, δ(CDCl₃): 1.6(s,6H), 4.6(s,1H), 6.6-7.4(m,13H).

PREPARATION EXAMPLE 19 Preparation of Exemplified Compound No. 41

In a similar manner to Preparation Example 1 except for the replacement of methyl chloroformate by 2,4-dimethylphenyl chloroformate, 2-(4'-hydroxyphenyl)2-[4"-(2,4-dimethylphenyl)oxycarbonylaminophenyl]-propane was obtained.

Melting Point: 156°-157° C.

¹ H-NMR, δ(CDCl₃): 1.6(s,6H), 2.2(s,3H), 2.4(s,3H), 5.0-5.1(br,1H), 6.6-7.4(m,12H).

PREPARATION EXAMPLE 20 Preparation of Exemplified Compound No. 62

In a similar manner to Preparation Example 1 except for the replacement of methyl chloroformate by S-phenyl chlorothioformate, 2-(4'-hydroxyphenyl)-2-(phenylthiolcarbonylaminophenyl)propane was obtained.

Melting Point: 118°-121° C.

¹ H-NMR, δ(CDCl₃): 1.6(s,6H), 5.3(s,1H), 6.6-7.5(m,14H).

PREPARATION EXAMPLE 21 Preparation of Exemplified Compound No. 65

Methyl chloroformate (11.4 g) was added dropwise to a suspension of 22.7 g of 2-(3'-hydroxyphenyl)-2-(4"-aminophenyl)propane and 5.3 g of sodium carbonate in 100 ml of ethyl acetate. After they were reacted at room temperature under stirring for 12 hours, the reaction mixture was filtered. Water (200 ml) was added to the resultant filtrate to wash the same. That procedure was repeated until the water layer became neutral. The reaction mixture was allowed to separate into layers. The ethyl acetate layer was collected and, then, ethyl acetate was distilled off under reduced pressure at 40° C., whereby a slightly yellowish crude product was obtained in a solid form. The product was recrystallized from 100 ml of toluene and then dried at 40° C. for 24 hours, whereby 26.2 g of 2-(3'-hydroxyphenyl)-2-(4"-methoxycarbonylaminophenyl)propane were obtained as white crystals.

Yield: 92%.

Melting Point: 137°-139° C.

¹ H-NMR, δ(CDCl₃): 1.6(t,3H), 3.8(s,3H), 5.1(s,1H), 6.5-7.4(m,9H).

PREPARATION EXAMPLE 22 Preparation of Exemplified Compound No. 66

In a similar manner to Preparation Example 21 except for the replacement of methyl chloroformate by n-butyl chloroformate, 2-(3'-hydroxyphenyl)-2-(4"-n-butoxycarbonylaminophenyl)propane was obtained.

Melting Point: 101°-104° C.

¹ H-NMR, δ(CDCl₃): 0.8-1.1(t,3H), 1.6(s,6H), 1.7-1.9(m,2H), 4.0-4.2(t,2H), 5.0(s,1H), 6.5-7.4(m,9H).

PREPARATION EXAMPLE 23 Preparation of Exemplified Compound No. 70

In a similar manner to Preparation Example 21 except for the replacement of methyl chloroformate by phenyl chloroformate, 2-(3'-hydroxyphenyl)-2-(4"-phenyloxycarbonylaminophenyl)propane was obtained.

Melting Point: 119°-124° C..

¹ H-NMR, δ(CDCl₃): 1.6(s,6H), 5.0(br,1H), 6.6-7.5(m,14H).

PREPARATION EXAMPLE 24 Preparation of Exemplified Compound No. 77

In a similar manner to Preparation Example 21 except for the replacement of methyl chloroformate by 4-chlorophenyl chloroformate, 2-(3'-hydroxyphenyl)-2-[4"-(4-chlorophenyl)oxycarbonylaminophenyl]propane was obtained.

Melting Point: 112°-116° C.

¹ H-NMR, δ(CDCl₃): 1.6(s,3H), 5.0(br,1H), 6.6-7.5(m,13H).

PREPARATION EXAMPLE 25 Preparation of Exemplified Compound No. 78

In a similar manner to Preparation Example 21 except for the replacement of methyl chloroformate by 2-chlorophenyl chloroformate, 2-(3'-hydroxyphenyl)-2-[4"-(2-chlorophenyl)oxycarbonylaminophenyl]propane was obtained.

Melting Point: 95°-101° C.

¹ H-NMR, δ(CDCl₃): 1.6(s,3H), 5.0(br,1H), 6.6-7.5(m,13H).

PREPARATION EXAMPLE 26 Preparation of Exemplified Compound No. 117

Methyl chloroformate (5.2 g) was added dropwise to a suspension of 10.0 g of 4-(4'-aminophenoxy)phenol and 4.6 g of sodium hydrogencarbonate in 50 ml of ethyl acetate. They were reacted at room temperature under stirring for 12 hours. Water (100 ml) was thereafter added to the reaction mixture to wash the same. That procedure was repeated until the water layer became neutral. The reaction mixture was allowed to separate into layers. The ethyl acetate layer was collected and, then, ethyl acetate was distilled off under reduced pressure at 40° C., whereby a slightly yellowish crude product was obtained in a solid form. The product was recrystallized from 500 ml of toluene and then dried at 40° C. for 24 hours, whereby 11.0 g of 4-hydroxyphenyl-4'-methoxycarbonylaminophenyl ether were obtained as white crystals.

Yield: 85%.

Melting Point: 104°-108° C.

¹ H-NMR, δ(CDCl₃): 1.1(s,3H), 6.7-7.8(m,6H), 7.3-7.8(m,2H), 8.2(s,1H), 8.3-8.4(br,1H).

PREPARATION EXAMPLE 27 Preparation of Exemplified Compound No. 118

In a similar manner to Preparation Example 26 except for the replacement of methyl chloroformate by ethyl chloroformate, 4-hydroxyphenyl-4'-ethoxycarbonylaminophenyl ether was obtained.

Melting Point: 117°-118° C.

¹ H-NMR, δ(CDCl₃): 1.2(t,3H), 4.2(q,2H), 6.8-7.0(m,6H), 7.4-7.7(m,2H), 8.1(s,1H), 8.2-8.4(br,1H).

PREPARATION EXAMPLE 28 Preparation of Exemplified Compound No. 119

In a similar manner to Preparation Example 26 except for the replacement of methyl chloroformate by n-butyl chloroformate, 4-hydroxyphenyl-4'-n-butoxycarbonylaminophenyl ether was obtained.

Melting Point: 118°-119° C.

¹ H-NMR, δ(CDCl₃): 1.2-4.3(m,9H), 6.8-7.1(m,6H), 7.3-7.6(m,2H), 8.0(s,1H), 8.3-8.4(br,1H).

PREPARATION EXAMPLE 29 Preparation of Exemplified Compound No. 120

In a similar manner to Preparation Example 26 except for the replacement of methyl chloroformate by n-hexyl chloroformate, 4-hydroxyphenyl-4'-n-hexyloxycarbonylaminophenyl ether was obtained.

Melting Point: 120°-122° C.

¹ H-NMR, δ(CDCl₃): 1.1-4.1(m,13H), 6.4-6.9(m,6H), 7.4-7.6(m,2H), 8.1-8.3(br,1H), 8.3(s,1H)

PREPARATION EXAMPLE 30 Preparation of Exemplified Compound No. 121

In a similar manner to Preparation Example 26 except for the replacement of methyl chloroformate by n-hexadecyl chloroformate, 4-hydroxyphenyl-4'-n-hexadecyloxycarbonylaminophenyl ether was obtained.

Melting Point: 123°-124° C.

¹ H-NMR, δ(CDCl₃): 1.1-4.5(m,33H), 6.9-7.8(m,8H), 8.1(s,1H), 8.2-8.4(br,1H).

PREPARATION EXAMPLE 31 Preparation of Exemplified Compound No. 122

In a similar manner to PREPARATION EXAMPLE 26 except for the replacement of methyl chloroformate by 2-methoxyethyl chloroformate, 4-hydroxyphenyl-4'-(2-methoxyethyl)oxycarbonylaminophenyl ether was obtained.

Melting Point: 89°-90° C.

¹ H-NMR, δ(CDCl₃): 1.5(s,3H), 3.6-4.2(m,4H), 6.9-7.1(m,6H), 7.4-7.8(m,2H), 8.1(s,1H), 8.4-8.5(br,1H).

PREPARATION EXAMPLE 32 Preparation of Exemplified Compound No. 125

In a similar manner to Preparation Example 26 except for the replacement of methyl chloroformate by benzyl chloroformate, 4-hydroxyphenyl-4'-benzyloxycarbonylaminophenyl ether was obtained.

Melting Point: 148°-150° C.

¹ H-NMR, δ(CDCl₃): 4.2(s,2H), 6.9-7.8(m,13H), 8.2(s,1H), 9.0-9.2(br,1H)

PREPARATION EXAMPLE 33 Preparation of Exemplified Compound No. 126

In a similar manner to Preparation Example 26 except for the replacement of methyl chloroformate by phenyl chloroformate, 4-hydroxyphenyl-4'-phenyloxycarbonylaminophenyl ether was obtained.

Melting Point: 158°-166° C.

¹ H-NMR, δ(CDCl₃): 6.8-7.6(m,13H), 8.2(s,1H), 8.9-9.2(br,1H).

PREPARATION EXAMPLE 34 Preparation of Exemplified Compound No. 128

In a similar manner to Preparation Example 26 except for the replacement of methyl chloroformate by 4-phenylphenyl chloroformate, 4-hydroxyphenyl-4'-(4-phenylphenyl)oxycarbonylaminophenyl ether was obtained.

Melting Point: 264°-270° C.

¹ H-NMR, δ(CDCl₃): 6.4-7.9(m,17H), 8.2(s,1H), 8.9-9.2(br,1H).

PREPARATION EXAMPLE 35 Preparation of Exemplified Compound No. 131

In a similar manner to Preparation Example 26 except for the replacement of methyl chloroformate by 3-chlorophenyl chloroformate, 4-hydroxyphenyl-4'-(3-chlorophenyl)oxycarbonylaminophenyl ether was obtained.

Melting Point: 121°-125° C.

¹ H-NMR, δ(CDCl₃): 6.8-7.9(m,12H), 8.4(s,1H), 8.7-9.1(br,1H).

PREPARATION EXAMPLE 36 Preparation of Exemplified Compound No. 134

In a similar manner to Preparation Example 26 except for the replacement of methyl chloroformate by S-phenyl chlorothioformate, 4-hydroxyphenyl-4'-phenylthiolcarbonylaminophenyl ether was obtained.

Melting Point: 138°-140° C.

¹ H-NMR, δ(CDCl₃): 6.6-7.9(m,13H), 8.1(s,1H), 9.0-9.2(br,1H).

PREPARATION EXAMPLE 37 Preparation of Exemplified Compound No. 136

Methyl chloroformate (11.3 g) was added dropwise to a suspension of 20.0 g of 3-(4'-aminophenoxy)phenol and 9.2 g of sodium hydrogencarbonate in 100 ml of ethyl acetate. They were reacted at room temperature under stirring for 9 hours. Water (100 ml) was thereafter added to the reaction mixture to wash the same. That procedure was repeated until the water layer became neutral. The reaction mixture was allowed to separate into layers. The ethyl acetate layer was collected and, then, ethyl acetate was distilled off under reduced pressure at 40° C., whereby a slightly brownish crude product was obtained in a solid form. The product was recrystallized from 700 ml of toluene and then dried at 40° C. for 24 hours, whereby 21.7 g of 3-hydroxyphenyl-4'-methoxycarbonylaminophenyl ether were obtained as white crystals.

Yield: 80%.

Melting Point: 95°-96° C.

¹ H-NMR, δ(CDCl₃): 1.1(s,3H), 6.7-7.1(m,6H), 7.3-7.8(m,8H), 8.5(s,1H), 9.0-9.3(br,1H).

PREPARATION EXAMPLE 38 Preparation of Exemplified Compound No. 137

In a similar manner to Preparation Example 37 except for the replacement of methyl chloroformate by ethyl chloroformate, 3-hydroxyphenyl-4'-ethoxycarbonylaminophenyl ether was obtained.

Melting Point: 126°-128° C.

¹ H-NMR, δ(CDCl₃): 1.2(t,3H), 4.1(q,2H), 6.3-7.8(m,8H), 8.3-8.7(m,2H).

PREPARATION EXAMPLE 39 Preparation of Exemplified Compound No. 138

In a similar manner to Preparation Example 37 except for the replacement of methyl chloroformate by n-octyl chloroformate, 3-hydroxyphenyl-4'-n-octyloxycarbonylaminophenyl ether was obtained.

Melting Point: 102°-104° C.

PREPARATION EXAMPLE 40 Preparation of Exemplified Compound No. 140

In a similar manner to Preparation Example 37 except for the replacement of methyl chloroformate by phenyl chloroformate, 3-hydroxyphenyl-4'-phenyloxycarbonylaminophenyl ether was obtained.

Melting Point: 132°-134° C.

¹ H-NMR, δ(CDCl₃): 6.3-6.7(m,5H), 6.9-7.8(m,8H), 8.5(s,1H), 9.0-9.3(br,1H).

PREPARATION EXAMPLE 41 Preparation of Exemplified Compound No. 144

In a similar manner to Preparation Example 37 except for the replacement of methyl chloroformate by 4-methoxyphenyl chloroformate, 3-hydroxyphenyl-4'-(3-methoxyphenyl)oxycarbonylaminophenyl ether was obtained.

Melting Point: 133°-136° C..

PREPARATION EXAMPLE 42 Preparation of Exemplified Compound No. 145

In a similar manner to Preparation Example 37 except for the replacement of methyl chloroformate by 3-chlorophenyl chloroformate, 3-hydroxyphenyl-4'-(3-chlorophenyl)oxycarbonylaminophenyl ether was obtained.

Melting Point: 101°-110° C.

¹ H-NMR, δ(CDCl₃): 6.5-7.6(m,5H), 6.9-7.8(m,7H), 8.6(s,1H), 9.0-9.3(br,1H).

PREPARATION EXAMPLE 43 Preparation of Exemplified Compound No. 157

Ethyl chloroformate (8.3 g) was added dropwise to a suspension of 14.9 g of 4-amino-4'-hydroxydiphenyl sulfide and 6.0 g of sodium hydrogencarbonate in 50 ml of ethyl acetate. They were reacted at room temperature under stirring for 12 hours. Water (200 ml) was thereafter added to the reaction mixture t wash the same. That procedure was repeated until the water layer became neutral. The reaction mixture was allowed to separate into layers. The ethyl acetate layer was collected and, then, ethyl acetate was distilled off under reduced pressure at 40° C., whereby a slightly yellowish crude product was obtained in a solid form. The product was recrystallized from 500 ml of toluene and then dried at 40° C. for 24 hours, whereby 17.3 g of 4-hydroxyphenyl-4'-ethoxycarbonylaminophenyl sulfide were obtained as white crystals.

Yield: 87%.

Melting Point: 87°-88° C.

¹ H-NMR, δ(CDCl₃): 1.3(t,3H), 4.2(q,2H), 5.3(br,1H), 6.7-6.9(m,3H), 7.0-7.4(m,6H).

PREPARATION EXAMPLE 44 Preparation of Exemplified Compound No. 158

In a similar manner to Preparation Example 43 except for the replacement of ethyl chloroformate by isobutyl chloroformate, 4-hydroxyphenyl-4'-isobutoxycarbonylaminophenyl sulfide was obtained.

Yield: 64%.

Melting point: 114°-116° C.

¹ H-NMR, δ(CDCl₃): 0.9(d,6H), 1.8-2.0(m,1H), 3.9(d,2H), 5.1(br,1H), 6.7-6.9(m,3H), 7.1-7.4(m,6H).

PREPARATION EXAMPLE 45 Preparation of Exemplified Compound No. 159

In a similar manner to Preparation Example 43 except for the replacement of ethyl chloroformate by n-hexadecyl chloroformate, 4-hydroxyphenyl-4'-n-hexadecyloxycarbonylaminophenyl sulfide was obtained.

Yield: 83%.

Melting Point: 114°-116° C.

¹ H-NMR, δ(CDCl₃): 1.3(br,31H), 4.1(t,2H), 5.0(br,1H), 6.7-6.9(m,3H), 7.2-7.4(m,6H).

PREPARATION EXAMPLE 46 Preparation of Exemplified Compound No. 161

In a similar manner to Preparation Example 43 except for the replacement of ethyl chloroformate by 2-methoxyethyl chloroformate, 4-hydroxyphenyl-4'-(2-methoxyethyl)oxycarbonylaminophenyl sulfide was obtained.

Melting Point: 82°-84° C.

¹ H-NMR, δ(CDCl₃): 3.4(s,3H), 3.6-3.7(m,2H), 4.3-4.4(m,2H), 5.2(br,1H), 6.6-6.9(m,3H), 7.1-7.7(m,6H).

PREPARATION EXAMPLE 47 Preparation of Exemplified Compound No. 165

In a similar manner to preparation Example 43 except for the replacement of ethyl chloroformate by phenyl chloroformate, 4-hydroxyphenyl-4'phenyloxycarbonylaminophenyl sulfide was obtained.

Melting Point: 151°-153° C.

¹ H-NMR, δ(CDCl₃): 4.9(br,1H), 6.7-6.9(m,3H), 7.1-7.6(m,11H)

PREPARATION EXAMPLE 48 Preparation of Exemplified Compound No. 172

In a similar manner to Preparation Example 43 except for the replacement of ethyl chloroformate by S-phenyl chlorothioformate, 4-hydroxyphenyl-4'phenylthiolcarbonylaminophenyl sulfide was obtained.

Melting Point: 243°-248° C.

¹ H-NMR, δ(CDCl₃): 5.1(br,1H), 6.8-6.9(m,3H), 7.3-7.8(m,11H)

PREPARATION EXAMPLE 49 Preparation of Exemplified Compound No. 192

Phenyl chloroformate (15.0 g) was added dropwise to a suspension of 26.4 g of 4"-aminophenyl-4-(4'-hydroxy)phenylbenzoate and 8.0 g of sodium hydrogencarbonate in 120 ml of ethyl acetate. They were reacted at room temperature under stirring for 12 hours. Water (300 ml) was thereafter added to the reaction mixture to wash the same. That procedure was repeated until the water layer became neutral. The reaction mixture was allowed to separate into layers. The ethyl acetate layer was collected and, then, ethyl acetate was distilled off under reduced pressure at 40° C., whereby a slightly yellowish crude product was obtained in a solid form. The product was recrystallized from 900 ml of toluene and then dried at 40° C. for 24 hours, whereby 27.7 g of 4"-phenyloxycarbonylaminophenyl-4-(4'-hydroxy)phenylbenzoate were obtained as white crystals.

Yield: 75%

Melting Point: >300° C.

¹ H-NMR, δ(CDCl₃): 6.8-7.6(m,17H), 8.2(s,1H), 8.9-9.2(br,1H)

PREPARATION EXAMPLE 50 Preparation of Exemplified Compound No. 193

Phenyl chloroformate (7.5 g) was added dropwise to a suspension of 13.2 of 3"-aminophenyl-4-(4'-hydroxy)phenylbenzoate and 4.0 g of sodium hydrogencarbonate in 50 ml of ethyl acetate. They were reacted at room temperature under stirring for 12 hours. Water (200 ml) was thereafter added to the reaction mixture to wash layer became neutral. The reaction mixture was allowed to separate into layers. The ethyl acetate layer was collected and, then, ethyl acetate was distilled off under reduced pressure at 40° C., whereby a slightly yellowish crude product was obtained in a solid form. The product was recrystallized from 500 ml of toluene and then dried at 40° C. for 24 hours, whereby 13.9 g of 3"-phenyloxycarbonylaminopheyl-4-(4'-hydroxy)phenylbenzoate were obtained as white crystals.

Yield: 75%.

Melting Point: >300° C.

¹ H-NMR, δ(CDCl₃): 6.8-7.6(m,17H), 8.2(s,1H), 8.9-9.2(br,1H)

PREPARATION EXAMPLE 51 Preparation of Exemplified Compound No. 194

Ethyl chloroformate (7.7 g) was added dropwise to a suspension of 14.9 g of 4'-hydroxyphenyl-4-aminobenzoate and 6.0 g of sodium hydrogencarbonate in 50 ml of ethyl acetate. They were reacted at room temperature under stirring for 12 hours. Water (200 ml) was thereafter added to the reaction mixture to wash the same. That procedure was repeated until the water layer became neutral. The reaction mixture was allowed to separate into layers. The ethyl acetate layer was collected and, then, ethyl acetate was distilled off under reduced pressure at 40° C., whereby a slightly yellowish crude product was obtained in a solid form. The product was recrystallized from 500 ml of toluene and then dried at 40° C. for 24 hours, whereby 14.9 g of 4'-hydroxyphenyl-4-ethoxycarbonylaminobenzoate were obtained as white crystals.

Yield: 76%.

Melting Point: >300° C.

¹ H-NMR, δ(CDCl₃): 1.2(t,3H), 4.2(q,2H) 6.8-7.0(m,6H), 7.4-7.7(m,2H), 8.1(s,1H), 8.2-8.4(br,1H).

Evaluation methods for heat-sensitive recording paper Storage stability test of produced color image

Using a color-producing apparatus for heat-sensitive recording paper ("TH-PMD", trade name; manufactured by Okura Denki K. K.), a color image having a color density of 0.9 as measured by a Macbeth densitometer ("TR-524 Model") was formed on a heat-sensitive recording paper produced in each of the below-described examples. Each heat-sensitive recording paper was then observed as to whether the image area presented the whitening phenomenon or not, and was then subjected to the below-described storage stability tests.

1. Heat resistance test

After each heat-sensitive recording paper had been stored at 60° C. for 24 hours, the density of the produced color image was measured by the Macbeth densitometer so that the percent remainder of the produced color image was determined.

2. Hydrothermoresistance test

After each heat-sensitive recording paper had been stored at 60° C. and 90% R. H. for 24 hours, the density of the produced color image was measured by the Macbeth densitometer so that the percent remainder of the produced color image was determined.

3. Waterproofness test

After each heat-sensitive recording paper had been stored at 25° C. for 24 hours in water, the density of the produced color image was measured by the Macbeth densitometer so that the percent remainder of the produced color image was determined.

4. Oil resistance test

Each heat-sensitive recording paper and a paper, which was coated with dioctyl-phthalate-containing capsules were brought into a contiguous relationship and then caused to pass through a pressure roll. After the heat-sensitive recording paper had been stored at 25° C. for 1 week, the density of the color image so produced was measured by the Macbeth densitometer so that the percent remainder of the produced color image was determined.

The percent remainder of each produced color image after each test was determined in accordance with the following formula: ##EQU1##

A greater value indicates better storage stability of produced color image.

Color-producing performance test

Each heat-sensitive recording paper was maintained for 5 seconds in contact with a metal block heated at a surface temperature of 150° C. The density of a color image so produced was measured using the Macbeth densitometer ("TR-524" Model). A greater value indicates a higher color density. From the practical viewpoint, the density of each color image so produced is considered to be sufficient as long a it is not smaller than 1.

Temperature-dependent color-producing performance

Each heat-sensitive recording paper was maintained for 5 minutes in contact with metal blocks heated at varied surface temperatures. The densities of color images so produced were measured using the Macbeth densitometer ("TR-524" Model). A greater value indicates a higher color density.

EXAMPLES 1-34

    ______________________________________                                         (Production method of heat-sensitive recording papers)                         ______________________________________                                         (Composition of Liquid A)                                                      Electron-donating chromogenic compound                                                                 10 g                                                   10% Aqueous solution of polyvinyl                                                                      10 g                                                   alcohol ("Kuraray-117", trade name;                                            product of Kuraray Co., Ltd.)                                                  Water                   80 g                                                   Total                   100 g                                                  (Composition of Liquid B)                                                      Electron-attracting compound                                                                           20 g                                                   Precipitated calcium carbonate                                                                         40 g                                                   ("TP-123", trade name; product of                                              Okutama Kogyo K.K.)                                                            10% Aqueous solution of polyvinyl                                                                      60 g                                                   alcohol ("Kuraray-117", trade name;                                            product of Kuraray Co., Ltd.)                                                  Water                   130 g                                                  Total                   250 g                                                  ______________________________________                                    

Liquid A and Liquid B were separately dispersed to an average particle size of 1.5 μm or smaller in a sand grinding mil, whereby dispersions were prepared. Mixed were the dispersion of 100 g of Liquid A, the dispersion of 250 g of Liquid B, and 23 g of 30% paraffin wax. The coating formulation so prepared was coated on a wood free paper to give a dry coat weight of 5.0±0.5 g/m² and then dried, whereby a heat-sensitive recording paper was produced.

Using the electron-donating chromogenic compounds and electron-attracting compounds [the compounds represented by the formula (1) or (2)], both shown in Tables 1(1) to 1(5), heat-sensitive recording papers were produced in the manner described above.

                  TABLE 1                                                          ______________________________________                                                                   Electron-attract-                                                              ing compound                                               Electron-donating   [Compound of                                         Ex.   chromogenic compound                                                                               formula (1) or (2)]                                  ______________________________________                                          1    3-Di-n-butylamino-6-methyl-                                                                        Exemplified                                                7-anilinofluoran    Compound No. 1                                        2    3-Diethylamino-6-methyl-                                                                           Exemplified                                                7-anilinofluoran    Compound No. 18                                       3    3-Di-n-butylamino-6-methyl-                                                                        Exemplified                                                7-anilinofluoran    Compound No. 24                                       4    3-N-isopentyl-N-ethylamino-                                                                        Exemplified                                                6-methyl-7-anilinofluoran                                                                          Compound No. 28                                       5    3-Di-n-butylamino-6-methyl-                                                                        Exemplified                                                7-anilinofluoran    Compound No. 33                                       6    3-N-isopentyl-N-ethylamino-                                                                        Exemplified                                                6-methyl-7-anilinofluoran                                                                          Compound No. 66                                       7    3-N-isopentyl-N-ethylamino-                                                                        Exemplified                                                6-methyl-7-anilinofluoran                                                                          Compound No. 70                                       8    3-N-isopentyl-N-ethylamino-                                                                        Exemplified                                                6-methyl-7-anilinofluoran                                                                          Compound No. 77                                       9    3-N-n-propyl-N-methylamino-                                                                        Exemplified                                                6-methyl-7-anilinofluoran                                                                          Compound No. 78                                      10    3-N-isobutyl-N-methylamino-                                                                        Exemplified                                                6-methyl-7-anilinofluoran                                                                          Compound No. 96                                      11    3-di-n-butylamino-6-methyl-                                                                        Exemplified                                                7-anilinofluoran    Compound No. 98                                      12    3-N-isopentyl-N-ethylamino-                                                                        Exemplified                                                6-methyl-7-anilinofluoran                                                                          Compound No. 99                                      13    3-Di-n-butylamino-6-methyl-                                                                        Exemplified                                                7-anilinofluoran    Compound No. 24 &                                                              Exemplified                                                                    Compound No. 70                                                                (50% : 50%)                                          14    3-Di-n-butylamino-6-methyl                                                                         Exemplified                                                7-anilinofluoran    Compound No. 117                                     15    3-Diethylamino-6-methyl-                                                                           Exemplified                                                7-anilinofluoran    Compound No. 119                                     16    3-Di-n-butylamino-6-methyl-                                                                        Exemplified                                                7-anilinofluoran    Compound No. 120                                     17    3-N-isopentyl-N-ethylamino-                                                                        Exemplified                                                6-methyl-7-anilinofluoran                                                                          Compound No. 121                                     18    3-Di-n-butylamino-6-methyl-                                                                        Exemplified                                                7-anilinofluoran    Compound No. 122                                     19    3-N-isopentyl-N-ethylamino-                                                                        Exemplified                                                6-methyl-7-anilinofluoran                                                                          Compound No. 125                                     20    3-N-isopentyl-N-ethylamino-                                                                        Exemplified                                                6-methyl-7-anilinofluoran                                                                          Compound No. 126                                     21    3-N-isopentyl-N-ethylamino-                                                                        Exemplified                                                6-methyl-7-anilinofluoran                                                                          Compound No. 128                                     22    3-N-n-propyl-N-methylamino-                                                                        Exemplified                                                6-methyl-7-anilinofluoran                                                                          Compound No. 131                                     23    3-N-isobutyl-N-methylamino-                                                                        Exemplified                                                6-methyl-7-anilinofluoran                                                                          Compound No. 136                                     24    3-Di-n-butylamino-6-methyl-                                                                        Exemplified                                                7-anilinofluoran    Compound No. 137                                     25    3-N-isopentyl-N-ethylamino-                                                                        Exemplified                                                6-methyl-7-anilinofluoran                                                                          Compound No. 140                                     26    3-Di-n-butylamino-6-methyl-                                                                        Exemplified                                                7-anilinofluoran    Compound No. 120 &                                                             Exemplified                                                                    Compound No. 126                                                               (50% : 50%)                                          27    3-Di-n-butylamino-6-methyl-                                                                        Exemplified                                                7-anilinofluoran    Compound No. 158                                     28    3-N-2'-methoxyethyl-N-                                                                             Exemplified                                                isobutylamino-6-methyl-7-                                                                          Compound No. 165                                           anilinofluoran                                                           29    3-N-isopentyl-N-ethylamino-                                                                        Exemplified                                                6-methyl-7-anilinofluoran                                                                          Compound No. 172                                     30    3-Di-n-butylamino-6-methyl-                                                                        Exemplified                                                7-anilinofluoran    Compound No. 221                                     31    3-Di-n-butylamino-7-(2-                                                                            Exemplified                                                chloroanilino)fluoran                                                                              Compound No. 234                                     32    3-Di-n-butylamino-6-methyl-                                                                        Exemplified                                                7-anilinofluoran    Compound No. 281                                     33    3-N-isopentyl-N-ethylamino-                                                                        Exemplified                                                6-methyl-7-anilinofluoran                                                                          Compound No. 352                                     34    3-Di-n-butylamino-6-methyl-                                                                        Exemplified                                                7-anilinofluoran    Compound No. 381                                     ______________________________________                                    

COMPARATIVE EXAMPLES 1-8

In each comparative example, heat-sensitive recording paper was produced in the above-described manner by using the electron-donating chromogenic compound and electron-attracting compound shown in Table 2.

                  TABLE 2                                                          ______________________________________                                         Comp.  Electron-donating  Electron-attract-                                    Ex.    chromogenic compound                                                                              ing compound                                         ______________________________________                                         1      3-Di-n-butylamino-6-methyl-                                                                       Bisphenol A                                                 7-anilinofluoran                                                        2      3-Di-n-butylamino-6-methyl-                                                                       Benzyl 4-hydroxy-                                           7-anilinofluoran   benzoate                                             3      3-N-isopentyl-N-ethylamino-                                                                       4-Benzyloxyphenol                                           6-methyl-7-anilinofluoran                                               4      3-Di-n-butylamino-6-methyl-                                                                       4-Hydroxybenzo-                                             7-anilinofluoran   phenone                                              5      3-Di-n-butylamino-6-methyl-                                                                       3-Ethoxycarbonyl-                                           7-anilinofluoran   aminophenol                                          6      3-Di-n-butylaminio-6-methyl-                                                                      4-Phenoxycarbo-                                             7-anilinofluoran   nylaminophenol                                       7      3-Di-n-butylamino-6-methyl-                                                                       4-tert-Butyl-                                               7-anilinofluoran   phenyloxycarbo-                                                                nylaminobenzene                                      8      3-Di-n-butylamino-6-methyl-                                                                       2,4-Bis(4'-tert-                                            7-anilinofluoran   butylphenyloxy-                                                                carbonylamino                                                                  toluene                                              ______________________________________                                    

Tables 3(1) to 3(3) present the results of incubation and waterproofness tests of color images produced on the heat-sensitive recording papers obtained in Examples 1-34 and Comparative Examples 1-6, respectively, and also show whether the color images were subjected to whitening or not.

                  TABLE 3                                                          ______________________________________                                         Storage Stability Test of                                                      Produced Color Image                                                                    Percent re- Percent re-                                               Heat-    mainder after                                                                              minder after                                              sensitive                                                                               hydrothermo-                                                                               waterproof-                                               recording                                                                               resistance  ness test                                                 paper    test (%)    (%)         Whitening                                     ______________________________________                                         Example 1                                                                               94          92          Not occurred                                  Example 2                                                                               96          95          Not occurred                                  Example 3                                                                               98          98          Not occurred                                  Example 4                                                                               98          96          Not occurred                                  Example 5                                                                               100         97          Not occurred                                  Example 6                                                                               95          93          Not occurred                                  Example 7                                                                               100         97          Not occurred                                  Example 8                                                                               98          96          Not occurred                                  Example 9                                                                               99          97          Not occurred                                  Example 10                                                                              98          97          Not occurred                                  Example 11                                                                              99          98          Not occurred                                  Example 12                                                                              98          97          Not occurred                                  Example 13                                                                              98          96          Not occurred                                  Example 14                                                                              81          90          Not occurred                                  Example 15                                                                              96          92          Not occurred                                  Example 16                                                                              98          94          Not occurred                                  Example 17                                                                              91          91          Not occurred                                  Example 18                                                                              79          93          Not occurred                                  Example 19                                                                              100         89          Not occurred                                  Example 20                                                                              100         95          Not occurred                                  Example 21                                                                              97          91          Not occurred                                  Example 22                                                                              100         96          Not occurred                                  Example 23                                                                              99          100         Not occurred                                  Example 24                                                                              98          93          Not occurred                                  Example 25                                                                              100         100         Not occurred                                  Example 26                                                                              96          96          Not occurred                                  Example 27                                                                              89          88          Not occurred                                  Example 28                                                                              88          89          Not occurred                                  Example 29                                                                              89          86          Not occurred                                  Example 30                                                                              90          85          Not occurred                                  Example 31                                                                              87          89          Not occurred                                  Example 32                                                                              90          88          Not occurred                                  Example 33                                                                              88          89          Not occurred                                  Example 34                                                                              87          87          Not occurred                                  Comp. Ex. 1                                                                             36          38          Not occurred                                  Comp. Ex. 2                                                                             26          25          Occurred                                      Comp. Ex. 3                                                                             30          25          Occurred                                      Comp. Ex. 4                                                                             24          20          Not occurred                                  Comp. Ex. 5                                                                             28          18          Not occurred                                  Comp. Ex. 6                                                                             30          21          Not occurred                                  ______________________________________                                    

As is apparent from Tables 3(1) to 3(3), the heat-sensitive recording papers of the present invention, which used the compound represented by the formula (1) or (2) as an electron-attracting compound, are extremely superior in the storage stability (hydrothermoresistance and waterproofness) of produced color images compared with the heat-sensitive recording materials produced using the conventional electro-attracting compound.

Tables 4(1) to 4(3) present the results of a color-producing performance test of the heat-sensitive recording papers obtained in Examples 1-34 and Comparative Examples 7-8.

                  TABLE 4                                                          ______________________________________                                         Color-Producing Performance Test                                                            Density of   Density of                                           Heat-sensitive                                                                              color-unproduced                                                                            produced color                                       recording paper                                                                             area         image                                                ______________________________________                                         Example 1    0.04         1.15                                                 Example 2    0.04         1.16                                                 Example 3    0.04         1.17                                                 Example 4    0.04         1.15                                                 Example 5    0.04         1.16                                                 Example 6    0.04         1.16                                                 Example 7    0.04         1.16                                                 Example 8    0.04         1.15                                                 Example 9    0.04         1.16                                                 Example 10   0.04         1.15                                                 Example 11   0.04         1.17                                                 Example 12   0.04         1.17                                                 Example 13   0.04         1.16                                                 Example 14   0.04         1.15                                                 Example 15   0.04         1.16                                                 Example 16   0.04         1.17                                                 Example 17   0.04         1.15                                                 Example 18   0.04         1.16                                                 Example 19   0.04         1.16                                                 Example 20   0.04         1.16                                                 Example 21   0.04         1.15                                                 Example 22   0.04         1.16                                                 Example 23   0.04         1.15                                                 Example 24   0.04         1.17                                                 Example 25   0.04         1.17                                                 Example 26   0.04         1.16                                                 Example 27   0.04         1.15                                                 Example 28   0.04         1.14                                                 Example 29   0.04         1.14                                                 Example 30   0.04         1.15                                                 Example 31   0.04         1.16                                                 Example 32   0.04         1.16                                                 Example 33   0.04         1.15                                                 Example 34   0.04         1.17                                                 Comp. Ex. 7  0.04         0.04                                                 Comp. Ex. 8  0.04         0.04                                                 ______________________________________                                    

As is evident from Tables 4(1) to 4(3), carbamate compounds without any intramolecular hydroxyl group can be considered to have absolutely no color-producing ability and to have practically no function as color-attracting compounds.

It is understood, on the other hand, that the compounds of this invention, which are represented by the formula (1) or (2), namely, the compounds with intramolecular hydroxyl and carbamate groups are electron-attracting compounds having valuable practical utility.

Table 5 presents the results of a color-producing performance test of the heat-sensitive recording materials, which were obtained in Examples 3, 15, 27 and 32 and Comparative Example 1, at varied temperatures.

                  TABLE 5                                                          ______________________________________                                         Color-Producing Performance                                                    Test at Varied Temperature                                                     Heat-sensitive                                                                            Temperature (°C.)                                            recording paper                                                                           100     105     110  115   120  130                                 ______________________________________                                         Example 3  0.04    0.25    0.82 1.05  1.17 1.17                                Example 15 0.05    0.28    0.80 1.06  1.15 1.15                                Example 27 0.05    0.26    0.80 1.04  1.15 1.15                                Example 32 0.04    0.27    0.83 1.06  1.16 1.16                                Comp. Ex. 1                                                                               0.05    0.10    0.15 0.21  0.35 1.10                                ______________________________________                                    

As is clearly envisaged from Table 5, the heat-sensitive recording materials according to the present invention promptly produced the color at lower temperatures than the heat-sensitive recording material using the conventional electron-attracting compound and are considered to be heat-sensitive recording materials of high sensitivity suited or high-speed recording.

EXAMPLES 35-71

    ______________________________________                                         (Production method of heat-sensitive recording papers)                         ______________________________________                                         (Composition of Liquid A')                                                     Electron-donating chromogenic compound                                                                 10 g                                                   10% Aqueous solution of polyvinyl                                                                      10 g                                                   alcohol ("Kuraray-117", trade name;                                            product of Kuraray Co., Ltd.)                                                  Water                   80 g                                                   Total                   100 g                                                  (Composition of Liquid B')                                                     Electron-attracting compound                                                                           20 g                                                   (bisphenol-A)                                                                  Precipitated calcium carbonate                                                                         40 g                                                   ("TP-123", trade name; product of                                              Okutama Kogyo K.K.)                                                            10% Aqueous solution of polyvinyl                                                                      60 g                                                   alcohol ("Kuraray-117", trade name;                                            product of Kuraray Co., Ltd.)                                                  Water                   130 g                                                  Total                   250 g                                                  (Composition of Liquid C')                                                     Compound of formula (1) or (2)                                                                         20 g                                                   10% Aqueous solution of polyvinyl                                                                      10 g                                                   alcohol ("Kuraray-117", trade name;                                            product of Kuraray Co., Ltd.)                                                  Water                   220 g                                                  Total                   250 g                                                  ______________________________________                                    

Liquid A', Liquid B' and Liquid C' were separately dispersed to an average particle size of 1.5 μm or smaller in a sand grinding mill, whereby dispersions were prepared.

Mixed were the dispersion of 100 g of Liquid A', the dispersion of 250 g of Liquid B', the dispersion of 250 g of Liquid C' and 23 g of 30% paraffin wax. The coating formulation so prepared was coated on a wood free paper to give a dry coat weight of 5.0±0.5 g/m² and then dried, whereby a heat-sensitive recording paper was produced.

Using the electron-donating chromogenic compounds and the compounds represented by the formula (1) or (2), both shown in Tables 6(1) to 6(5), heat-sensitive recording papers were produced in the manner described above.

                  TABLE 6                                                          ______________________________________                                                                   Compound of                                                Electron-donating   formula                                              Ex.   chromogenic compound                                                                               (1) or (2)                                           ______________________________________                                         35    3-Di-n-butylamino-6-methyl-                                                                        Exemplified                                                7-anilinofluoran    Compound No. 1                                       36    3-Diethylamino-6-methyl-                                                                           Exemplified                                                7-anilinofluoran    Compound No. 18                                      37    3-Di-n-butylamino-6-methyl-                                                                        Exemplified                                                7-anilinofluoran    Compound No. 24                                      38    3-N-isopentyl-N-ethylamino-                                                                        Exemplified                                                6-methyl-7-anilinofluoran                                                                          Compound No. 28                                      39    3-Di-n-butylamino-6-methyl-                                                                        Exemplified                                                7-anilinofluoran    Compound No. 33                                      40    3-N-isopentyl-N-ethylamino-                                                                        Exemplified                                                6-methyl-7-anilinofluoran                                                                          Compound No. 66                                      41    3-N-isopentyl-N-ethylamino-                                                                        Exemplified                                                6-methyl-7-anilinofluoran                                                                          Compound No. 70                                      42    3-N-isopentyl-N-ethylamino-                                                                        Exemplified                                                6-methyl-7-anilinofluoran                                                                          Compound No. 77                                      43    3-N-n-propyl-N-methylamino-                                                                        Exemplified                                                6-methyl-7-anilinofluoran                                                                          Compound No. 78                                      44    3-N-isobutyl-N-methylamino-                                                                        Exemplified                                                6-methyl-7-anilinofluoran                                                                          Compound No. 96                                      45    3-Di-n-butylamino-6-methyl-                                                                        Exemplified                                                7-anilinofluoran    Compound No. 98                                      46    3-N-isopentyl-N-ethylamino-                                                                        Exemplified                                                6-methyl-7-anilinofluoran                                                                          Compound No. 99                                      47    3-Di-n-butylamino-6-methyl-                                                                        Exemplified                                                7-anilinofluoran    Compound No. 24 &                                                              Exemplified                                                                    Compound No. 70                                                                (50% : 50%)                                          48    3-Di-n-butylamino-6-methyl                                                                         Exemplified                                                7-anilinofluoran    Compound No. 117                                     49    3-Diethylamino-6-methyl-                                                                           Exemplified                                                7-anilinofluoran    Compound No. 119                                     50    3-Di-n-butylamino-6-methyl-                                                                        Exemplified                                                7-anilinofluoran    Compound No. 120                                     51    3-N-isopentyl-N-ethylamino-                                                                        Exemplified                                                6-methyl-7-anilinofluoran                                                                          Compound No. 121                                     52    3-Di-n-butylamino-6-methyl-                                                                        Exemplified                                                7-anilinofluoran    Compound No. 122                                     53    3-N-isopentyl-N-ethylamino-                                                                        Exemplified                                                6-methyl-7-anilinofluoran                                                                          Compound No. 125                                     54    3-N-isopentyl-N-ethylamino-                                                                        Exemplified                                                6-methyl-7-anilinofluoran                                                                          Compound No. 126                                     55    3-N-isopentyl-N-ethylamino-                                                                        Exemplified                                                6-methyl-7-anilinofluoran                                                                          Compound No. 128                                     56    3-N-n-propyl-N-methylamino-                                                                        Exemplified                                                6-methyl-7-anilinofluoran                                                                          Compound No. 131                                     57    3-N-isobutyl-N-methylamino-                                                                        Exemplified                                                6-methyl-7-anilinofluoran                                                                          Compound No. 136                                     58    3-Di-n-butylamino-6-methyl-                                                                        Exemplified                                                7-anilinofluoran    Compound No. 137                                     59    3-N-isopentyl-N-ethylamino-                                                                        Exemplified                                                6-methyl-7-anilinofluoran                                                                          Compound No. 140                                     60    3-Di-n-butylamino-6-methyl-                                                                        Exemplified                                                7-anilinofluoran    Compound No. 120                                                               Exemplified                                                                    Compound No. 126                                                               (50% : 50%)                                          61    3-Di-n-butylamino-6-methyl-                                                                        Exemplified                                                7-anilinofluoran    Compound No. 158                                     62    3-N-2'-methoxyethyl-N-                                                                             Exemplified                                                isobutylamino-6-methyl-7-                                                                          Compound No. 165                                           anilinofluoran                                                           63    3-N-isopentyl-N-ethylamino-                                                                        Exemplified                                                6-methyl-7-anilinofluoran                                                                          Compound No. 172                                     64    3-Di-n-butylamino 6-methyl-                                                                        Exemplified                                                7-anilinofluoran    Compound No. 193                                     65    3-N-isopentyl-N-ethylamino-                                                                        Exemplified                                                6-methyl-7-anilinofluoran                                                                          Compound No. 194                                     66    3-Di-n-butylamino-6-methyl-                                                                        Exemplified                                                7-anilinofluoran    Compound No. 221                                     67    3-Di-n-butylamino-7-(2-                                                                            Exemplified                                                chloroanilino)fluoran                                                                              Compound No. 234                                     68    3-Di-n-butylamino-6-methyl-                                                                        Exemplified                                                7-anilinofluoran    Compound No. 281                                     69    3-Di-n-butylamino-6-methyl-                                                                        Exemplified                                                7-anilinofluoran    Compound No. 358                                     70    3-Di-n-butylamino-6-methyl-                                                                        Exemplified                                                7-anilinofluoran    Compound No. 375                                     71    3-Di-n-butylamino-6-methyl-                                                                        Exemplified                                                7-anilinofluoran    Compound No. 381                                     ______________________________________                                    

COMPARATIVE EXAMPLES 9-10

In each comparative example, heat-sensitive recording paper was produced in the above-described manner by using the electron-donating chromogenic compound shown in Table 7 and Liquids A' and B' without using Liquid C'.

                  TABLE 7                                                          ______________________________________                                                        Electron-donating                                               Comp. Ex.      chromogenic compound                                            ______________________________________                                          9             3-Di-n-butylamino-6-methyl-                                                    7-anilinofluoran                                                10             3-N-isopentyl-N-ethylamino-                                                    6-methyl-7-anilinofluoran                                       ______________________________________                                    

COMPARATIVE EXAMPLES 11-19

In each comparative example, heat-sensitive recording paper was produced in substantially the same manner as described above except that 3-di-n-butylamino-6-methyl-7-anilinofluoran was used as the electron-donating chromogenic compound in Liquid A' and the compound shown in Table 8 was used in place of the compound of the general formula (1) or (2) in Liquid C'.

                  TABLE 8                                                          ______________________________________                                         Comp. Ex.  Compound in Liquid C'                                               ______________________________________                                         11         4-Benzylbiphenyl                                                    12         m-Terphenyl                                                         13         3-Ethoxycarbonylaminophenol                                         14         4-Phenyloxycarbonylaminophenol                                      15         4-tert-Butylphenyloxycarbonylamino-                                            benzene                                                             16         4-Cumylphenyloxycarbonylaminobenzene                                17         1,6-Bis(phenyloxycarbonylamino)hexane                               18         1,1-Bis(4-ethoxycarbonylaminophenyl)-                                          methane                                                             19         Di-(4-ethoxycarbonylaminophenyl)ether                               ______________________________________                                    

Tables 9(1) to 9(3) present the results of incubation, waterproofness and oil resistance tests of color images produced on the heat-sensitive recording papers obtained in Examples 35-71 and Comparative Examples 9-19.

                  TABLE 9                                                          ______________________________________                                         Storage Stability Test of                                                      Produced Color Image                                                                     Percent re-                                                                               Percent re- Percent re-                                   Heat-     mainder after                                                                             mainder after                                                                              mainder after                                 sensitive hydrothermo-                                                                              waterproof- oil resis-                                    recording resistance ness test   tance test                                    paper     test (%)   (%)         (%)                                           ______________________________________                                         Example 35                                                                               100        98          99                                            Example 36                                                                               100        97          96                                            Example 37                                                                               99         97          98                                            Example 38                                                                               99         100         98                                            Example 39                                                                               100        97          99                                            Example 40                                                                               98         99          99                                            Example 41                                                                               100        97          100                                           Example 42                                                                               98         96          97                                            Example 43                                                                               100        97          99                                            Example 44                                                                               98         99          99                                            Example 45                                                                               100        98          99                                            Example 46                                                                               99         97          98                                            Example 47                                                                               98         98          98                                            Example 48                                                                               81         90          90                                            Example 49                                                                               96         90          94                                            Example 50                                                                               98         92          94                                            Example 51                                                                               91         94          96                                            Example 52                                                                               79         91          95                                            Example 53                                                                               100        93          99                                            Example 54                                                                               100        89          85                                            Example 55                                                                               97         95          96                                            Example 56                                                                               100        91          100                                           Example 57                                                                               99         96          98                                            Example 58                                                                               98         100         89                                            Example 59                                                                               100        93          92                                            Example 60                                                                               96         96          93                                            Example 61                                                                               95         93          90                                            Example 62                                                                               95         94          89                                            Example 63                                                                               96         94          88                                            Example 64                                                                               98         93          90                                            Example 65                                                                               98         92          91                                            Example 66                                                                               97         90          90                                            Example 67                                                                               95         92          86                                            Example 68                                                                               95         91          88                                            Example 69                                                                               94         92          90                                            Example 70                                                                               94         93          87                                            Example 71                                                                               90         90          91                                            Comp. Ex. 9                                                                              36         38          20                                            Comp. Ex. 10                                                                             42         45          29                                            Comp. Ex. 11                                                                             18         15          16                                            Comp. Ex. 12                                                                             16         13          12                                            Comp. Ex. 13                                                                             19         18          11                                            Comp. Ex. 14                                                                             20         19          15                                            Comp. Ex. 15                                                                             21         20          17                                            Comp. Ex. 16                                                                             23         21          19                                            Comp. Ex. 17                                                                             22         20          16                                            Comp. Ex. 18                                                                             20         17          17                                            Comp. Ex. 19                                                                             19         18          18                                            ______________________________________                                    

As is apparent from Tables 9(1) to 9(3), the heat-sensitive recording materials according to the present invention are excellent in the storage stability (hydrothermoresistance, waterproofness and oil resistance) of produced color images.

Table 10 shows the results of a color-producing performance test of the heat-sensitive recording papers, which were obtained in Examples 37, 49, 61 and 68 and Comparative Example 9, at varied temperatures.

                  TABLE 10                                                         ______________________________________                                         Color-Producing Performance                                                    Test at Varied Temperatures                                                    Heat-                                                                          sensitive                                                                      recording                                                                               Temperature (°C.)                                              paper    95      100     105   110   120   130                                 ______________________________________                                         Example 37                                                                              0.10    0.68    1.10  1.26  1.35  1.35                                Example 49                                                                              0.10    0.68    1.10  1.26  1.35  1.35                                Example 61                                                                              0.10    0.66    1.11  1.20  1.35  1.35                                Example 68                                                                              0.10    0.65    1.12  1.22  1.35  1.35                                Comp. Ex. 9                                                                             0.05    0.05    0.10  0.15  0.35  1.10                                ______________________________________                                    

As is understood clearly from Table 10, the heat-sensitive recording materials according to the present invention promptly produced the color at lower temperatures than the heat-sensitive recording material composed of the conventional electron-attracting chromogenic compound and electron-attracting compound and are considered to be heat-sensitive recording materials of high sensitivity suitable for high-speed recording.

EXAMPLES 72-108 Production method of heat-sensitive recording papers

In each example, heat-sensitive recording paper was produced in the above-described manner by using 100 g of Liquid A", 250 g of Liquid B", 250 g of Liquid C" and 23 g of 30% paraffin wax. Liquids A", B" and C" had been prepared using the electron-donating chromogenic compound, thermofusible compound and the compound of the formula ) or (2), all shown in Table 11.

    ______________________________________                                         (Composition of Liquid A")                                                     Electron-donating chromogenic compound                                                                 10 g                                                   10% Aqueous solution of polyvinyl                                                                      10 g                                                   alcohol ("Kuraray-117", trade name;                                            product of Kuraray Co., Ltd.)                                                  Water                   80 g                                                   Total                   100 g                                                  (Composition of Liquid B")                                                     Electron-attracting compound                                                                           20 g                                                   (bisphenol-A)                                                                  Precipitated calcium carbonate                                                                         40 g                                                   ("TP-123", trade name; product of                                              Okutama Kogyo K.K.)                                                            10% Aqueous solution of polyvinyl                                                                      60 g                                                   alcohol ("Kuraray-117", trade name;                                            product of Kuraray Co., Ltd.)                                                  Water                   130 g                                                  Total                   250 g                                                  (Composition of Liquid C")                                                     Thermofusible compound   5 g                                                   Compound of formula (1) or (2)                                                                         15 g                                                   10% Aqueous solution of polyvinyl                                                                      10 g                                                   alcohol ("Kuraray-117", trade name;                                            product of Kuraray Co., Ltd.)                                                  Water                   220 g                                                  Total                   250 g                                                  ______________________________________                                    

                  TABLE 11                                                         ______________________________________                                                                 Thermo-                                                                        fusible  Compound of                                        Electron-donating  com-     formula                                       Ex.  chromogenic compound                                                                              pound    (1) or (2)                                    ______________________________________                                         72   3-Di-n-butylamino-6-methyl-                                                                       A        Exemplified                                        7-anilinofluoran            Compound                                                                       No. 1                                         73   3-Diethylamino-6-methyl-                                                                          A        Exemplified                                        7-anilinofluoran            Compound                                                                       No. 18                                        74   3-Di-n-butylamino-6-methyl-                                                                       A        Exemplified                                        7-anilinofluoran            Compound                                                                       No. 24                                        75   3-N-isopentyl-N-ethylamino-                                                                       A        Exemplified                                        6-methyl-7-anilinofluoran   Compound                                                                       No. 28                                        76   3-Di-n-butylamino-6-methyl-                                                                       B        Exemplified                                        7-anilinofluoran            Compound                                                                       No. 33                                        77   3-N-isopentyl-N-ethylamino-                                                                       C        Exemplified                                        6-methyl-7-anilinofluoran   Compound                                                                       No. 66                                        78   3-N-isopentyl-N-ethylamino-                                                                       D        Exemplified                                        6-methyl-7-anilinofluoran   Compound                                                                       No. 70                                        79   3-N-isopentyl-N-ethylamino-                                                                       C        Exemplified                                        6-methyl-7-anilinofluoran   Compound                                                                       No. 77                                        80   3-N-n-propyl-N-methylamino-                                                                       A        Exemplified                                        6-methyl-7-anilinofluoran   Compound                                                                       No. 78                                        81   3-N-Isobutyl-N-methylamino-                                                                       E        Exemplified                                        6-methyl-7-anilinofluoran   Compound                                                                       No. 96                                        82   3-Di-n-butylamino-6-methyl-                                                                       D        Exemplified                                        7-anilinofluoran            Compound                                                                       No. 98                                        83   3-N-Isopentyl-N-ethylamino-                                                                       D        Exemplified                                        6-methyl-7-anilinofluoran   Compound                                                                       No. 99                                        84   3-Di-n-butylamino-6-methyl-                                                                       D        Exemplified                                        7-anilinofluoran            Compound                                                                       No. 24 &                                                                       Exemplified                                                                    Compound                                                                       No. 70                                                                         (50%:50%)                                     85   3-Di-n-butylamino-6-methyl-                                                                       A        Exemplified                                        7-anilinofluoran            Compound                                                                       No. 117                                       86   3-Diethylamino-6-methyl-                                                                          A        Exemplified                                        7-anilinofluoran            Compound                                                                       No. 119                                       87   3-Di-n-butylamino-6-methyl-                                                                       A        Exemplified                                        7-anilinofluoran            Compound                                                                       No. 120                                       88   3-N-Isopentyl-N-ethylamino-                                                                       A        Exemplified                                        6-methyl-7-anilinofluoran   Compound                                                                       No. 121                                       89   3-Di-n-butylamino-6-methyl-                                                                       B        Exemplified                                        7-anilinofluoran            Compound                                                                       No. 122                                       90   3-N-Isopentyl-N-ethylamino-                                                                       C        Exemplified                                        6-methyl-7-anilinofluoran   Compound                                                                       No. 125                                       91   3-N-Isopentyl-N-ethylamino-                                                                       D        Exemplified                                        6-methyl-7-anilinofluoran   Compound                                                                       No. 126                                       92   3-N-Isopentyl-N-ethylamino-                                                                       C        Exemplified                                        6-methyl-7-anilinofluoran   Compound                                                                       No. 128                                       93   3-N-n-Propyl-N-methylamino-                                                                       A        Exemplified                                        6-methyl-7-anilinofluoran   Compound                                                                       No. 131                                       94   3-N-Isobutyl-N-methylamino-                                                                       E        Exemplified                                        6-methyl-7-anilinofluoran   Compound                                                                       No. 136                                       95   3-Di-n-butylamino-6-methyl-                                                                       D        Exemplified                                        7-anilinofluoran            Compound                                                                       No. 137                                       96   3-N-Isopentyl-N-ethylamino-                                                                       D        Exemplified                                        6-methyl-7-anilinofluoran   Compound                                                                       No. 140                                       97   3-Di-n-butylamino-6-methyl-                                                                       D        Exemplified                                        7-anilinofluoran            Compound                                                                       No. 120 &                                                                      Exemplified                                                                    Compound                                                                       No. 126                                                                        (50%:50%)                                     98   3-Di-n-butylamino-6-methyl-                                                                       A        Exemplified                                        7-anilinofluoran            Compound                                                                       No. 158                                       99   3-N-2'-methoxyethyl-N-iso-                                                                        A        Exemplified                                        butylamino-6-methyl-7-      Compound                                           anilinofluoran              No. 165                                       100  3-N-isopentyl-N-ethylamino-                                                                       B        Exemplified                                        6-methyl-7-anilinofluoran   Compound                                                                       No. 172                                       101  3-Di-n-butylamino-6-methyl-                                                                       C        Exemplified                                        7-anilinofluoran            Compound                                                                       No. 193                                       102  3-N-isopentyl-N-ethylamino-                                                                       D        Exemplified                                        6-methyl-7-anilinofluoran   Compound                                                                       No. 194                                       103  3-Di-n-butylamino-6-methyl-                                                                       E        Exemplified                                        7-anilinofluoran            Compound                                                                       No. 221                                       104  3-Di-n-butylamino-7-(2-                                                                           A        Exemplified                                        chloroanilino)fluoran       Compound                                                                       No. 234                                       105  3-Di-n-butylamino-6-methyl-                                                                       A        Exemplified                                        7-anilinofluoran            Compound                                                                       No. 281                                       106  3-Di-n-butylamino-6-methyl-                                                                       A        Exemplified                                        7-anilinofluoran            Compound                                                                       No. 358                                       107  3-Di-n-butylamino-6-methyl-                                                                       A        Exemplified                                        7-anilinofluoran            Compound                                                                       No. 375                                       108  3-Di-n-butylamino-6-methyl-                                                                       A        Exemplified                                        7-anilinofluoran            Compound                                                                       No. 381                                       ______________________________________                                    

Incidentally, the thermofusible compounds A, B, C, D and E used in Tables 11(1) to 11(5) indicate the following compounds:

A: 2-Benzyloxynaphthalene

B: Di(4-methylbenzyl)oxalate

C: 1,2-Bis(3'-methylphenoxy)ethane

D: 4-(4'-Methylphenoxy)biphenyl

E: 4-Benzylbiphenyl

COMPARATIVE EXAMPLES 20-24

In each comparative example, heat-sensitive recording paper was produced in the above-described manner from 100 g of Liquid A", 250 g of Liquid B", g of Liquid D" in place of Liquid C", and 23 g of 30% paraffin wax. Liquid A" had been prepared by employing the electron-donating chromogenic compound shown in Table 12 while Liquid D" had been obtained using the thermofusible compound shown in Table 12 in accordance with the below-described composition.

    ______________________________________                                         (Composition of Liquid D")                                                     ______________________________________                                         Thermofusible compound  20 g                                                   10% Aqueous solution of polyvinyl                                                                      10 g                                                   alcohol ("Kuraray-117", trade name;                                            product of Kuraray Co., Ltd.)                                                  Water                  220 g                                                   Total                  250 g                                                   ______________________________________                                    

                  TABLE 12                                                         ______________________________________                                         Comp.    Electron-donating Thermofusible                                       Ex.      chromogenic compound                                                                             substance                                           ______________________________________                                         20       3-Di-n-butylamino-6-methyl-                                                                      A                                                            7-anilinofluoran  A                                                   21       3-N-Isopentyl-N-ethylamino-                                                                      A                                                            6-methyl-7-anilinofluoran                                             22       3-Di-n-butylamino-6-methyl-                                                                      B                                                            7-anilinofluoran                                                      23       3-Di-n-butylamino-6-methyl-                                                                      C                                                            7-anilinofluoran                                                      24       3-Di-n-butylamino-6-methyl-                                                                      D                                                            7-anilinofluoran                                                      ______________________________________                                    

Incidentally, the thermofusible compounds A, B, C and D employed in Table 12 indicate the following compounds:

A: 2-Benzyloxynaphthalene

B: Di(4-methylbenzyl) oxalate

C: 1,2-Bis(3'-methylphenoxy)ethane

D: 4-(4'-Methylphenoxy)biphenyl

COMPARATIVE EXAMPLE 25-26

In each comparative example, heat-sensitive recording paper was produced in the same manner as described above except that 3-di(n-butylamino)-6-methyl-7-anilinofluoran was used as the electron-donating chromogenic compound in Liquid A" and 3-ethoxycarbonylaminophenol (Comparative Example 25) or 4-phenyloxycarbonylaminobenzene (Comparative Example 26) was employed instead of the compound of the formula (1) or (2) in Liquid C".

Tables 13(1) to 13(5) present the results of heat resistance, incubation, Waterproofness and oil resistance tests of color images produced on the heat-sensitive recording papers obtained in Examples 72-108 and Comparative Examples 20-26, respectively.

                                      TABLE 13                                     __________________________________________________________________________     Storage Stability Test of Produced Color Image                                        Percent Percent remainder                                                                        Percent Percent                                       Heat-sensitive                                                                        remainder after                                                                        after hydro-                                                                             remainder after                                                                        remainder after                               recording                                                                             heat resistance                                                                        thermo-resistance                                                                        waterproofness                                                                         oil resistance                                paper  test (%)                                                                               test (%)  test (%)                                                                               test (%)                                      __________________________________________________________________________     Example 72                                                                            93      86        84      89                                            Example 73                                                                            91      88        85      84                                            Example 74                                                                            93      88        87      86                                            Example 75                                                                            92      90        86      84                                            Example 76                                                                            94      87        86      89                                            Example 77                                                                            91      91        88      87                                            Example 78                                                                            90      90        86      84                                            Example 79                                                                            93      91        86      87                                            Example 80                                                                            90      88        90      89                                            Example 81                                                                            90      86        84      83                                            Example 82                                                                            91      85        85      86                                            Example 83                                                                            93      88        87      88                                            Example 84                                                                            90      90        88      88                                            Example 85                                                                            90      88        88      89                                            Example 86                                                                            93      86        87      88                                            Example 87                                                                            91      90        85      88                                            Example 88                                                                            90      98        84      86                                            Example 89                                                                            90      85        90      83                                            Example 90                                                                            93      86        86      89                                            Example 91                                                                            90      88        86      87                                            Example 92                                                                            91      91        88      84                                            Example 93                                                                            94      90        86      89                                            Example 94                                                                            92      91        86      84                                            Example 95                                                                            93      87        87      86                                            Example 96                                                                            91      90        85      84                                            Example 97                                                                            93      88        84      87                                            Example 98                                                                            90      88        84      83                                            Example 99                                                                            89      87        83      82                                            Example 100                                                                           88      87        82      82                                            Example 101                                                                           89      86        85      82                                            Example 102                                                                           91      85        83      82                                            Example 103                                                                           90      84        82      82                                            Example 104                                                                           88      83        82      82                                            Example 105                                                                           90      88        84      83                                            Example 106                                                                           94      87        85      84                                            Example 107                                                                           90      88        85      84                                            Example 108                                                                           91      90        89      88                                            Com. Ex. 20                                                                           30      15        20      10                                            Com. Ex. 21                                                                           42      28        32      21                                            Com. Ex. 22                                                                           30      18        18      11                                            Com. Ex. 23                                                                           29      17        16      12                                            Com. Ex. 24                                                                           32      18        21      15                                            Com. Ex. 25                                                                           30      19        18      14                                            Com. Ex. 26                                                                           29      19        18      16                                            __________________________________________________________________________

As is clearly envisaged from Tables 13(1) to 13(5), the heat-sensitive recording materials according to the present invention are excellent in the storage stability (heat resistance, hydrothermoresistance, waterproofness and oil resistance) of produced color images.

Table 14 presents the results of a color-producing performance test of the heat-sensitive recording papers, which were obtained in Examples 74, 86, 98 and 105 and Comparative Example 20, at varied temperatures.

                  TABLE 14                                                         ______________________________________                                         Color-Producing Performance Test at Varied Temperatures                        Heat-                                                                          sensitive                                                                      recording                                                                               Temperature (°C.)                                              paper    75      80      85    90    95    100                                 ______________________________________                                         Example 74                                                                              0.05    0.10    0.80  0.93  1.09  1.21                                Example 86                                                                              0.05    0.10    0.80  0.93  1.09  1.21                                Example 98                                                                              0.05    0.11    0.82  0.95  1.10  1.20                                Example 105                                                                             0.05    0.11    0.81  0.92  1.12  1.22                                Comp. Ex. 20                                                                            0.05    0.07    0.10  0.20  0.92  1.19                                ______________________________________                                    

As is understood clearly from Table 14, the heat-sensitive recording materials according to the present invention promptly produced the color at lower temperatures than the conventional heat-sensitive recording material and are considered to be heat-sensitive recording materials of high sensitivity suitable for high-speed recording. 

What is claimed is:
 1. A heat-sensitive recording material containing an electron-donating chromogenic compound and an electron-attracting compound, comprising at least one of the compounds represented by the following formula (1) or (2): ##STR32## wherein R₁ and R₃ individually mean a hydrogen atom or an alkyl, aralkyl or aryl group, R₂ and R₄ individually denote an alkyl, alkenyl, aralkyl or aryl group, X₁, X₂, Y₁ and Y₂ stand for an oxygen or a sulfur atom, and --Z₁ -- and --Z₂ -- are a group represented by the following formula (i) or (ii): ##STR33## wherein R₅, R₆ and R₇ individually mean a hydrogen or halogen atom or an alkyl, alkoxy, aralkyl, aryl or hydroxyl group, p, q and r stand for an integer of 1-4, R₅, R₆ and R₇ may be either the same or different when p, q and r individually represent an integer of 2 or greater, the rings A and A' individually denote a benzene or naphthalene ring, the ring D represents a naphthalene ring, and --B-- represents a group containing at least one group selected from the class consisting of --R₈ CR₉ -- (in which R₈ and R₉ individually represent a hydrogen atom or an alkyl, trifluoromethyl or aryl group or are combined together to form a ring), --O--, --S--, a phenylene group, --CO--, a single bond, --C_(m) H_(2m) --, m integer of 2-10, CR₁₀ ═CR₁₁ -- (in which R₁₀ and R₁₁ are individually a hydrogen atom or an alkyl or aryl group), --SO--, and --SO₂ --.
 2. The material of claim 1, wherein in the formula (i) or (ii), --Z₁ -- or Z₂ -- is a group represented by the following formula (iii), (iv), (v), (vi), (vii), (viii) or (ix): ##STR34## wherein R₅, R₆, R₇, R₈, R₉, p, q and r have the same meanings as defined above.
 3. The material of claim 1, wherein in the formula (1), X₁ and Y₁ are an oxygen atom and --Z₁ -- is the following group (iii): ##STR35## wherein R₅ and R₆ are either the same or different and individually mean a hydrogen or halogen atom or an alkyl, alkoxy, aralkyl, aryl or hydroxyl group, R₈ and R₉ individually denote a hydrogen atom or an alkyl or aryl group or are combined together to form a ring, and p and q stand for
 2. 4. The material of claim 1, wherein in the formula (1), X₁ and Y₁ are an oxygen atom and --Z₁ -- is the following (iv): ##STR36## wherein R₅ and R₆ are either the same or different and individually mean a hydrogen or halogen atom or an alkyl, alkoxy, aralkyl or aryl group, and p and q stand for
 2. 